BASIC PRINCIPAL UNDERLYING BREATH TEST PROVEN UNTRUE

January 11, 2007 by alabamadui

The Impact of Breathing Pattern and Lung Size on the Alcohol Breath Test

MICHAEL P. HLASTALA
1,2,3 and JOSEPH C. ANDERSON4

1Department of Physiology and Biophysics, University of Washington, Box 356522, Seattle, WA 98195-6522, USA; 2Department of Medicine, University of Washington, Box 356522, Seattle, WA 98195-6522, USA; 3Division of Pulmonary and Critical Care
Medicine, University of Washington, Box 356522, Seattle, WA 98195-6522, USA; and 4Department of Bioengineering, University of Washington, Seattle, WA 98195-5061, USA (Received 21 March 2006; accepted 29 September 2006)

Abstract—Highly soluble gases exchange primarily with the bronchial circulation through pulmonary airway tissue. Because of this airway exchange, the assumption that end-exhaled alcohol concentration (EEAC) is equal to alveolar alcohol concentration (AAC) cannot be true. During exhalation, breath alcohol concentration (BrAC) decreases due to uptake of ethanol by the airway tissue. It is therefore impossible to deliver alveolar gas to the mouth
during a single exhalation without losing alcohol to the
airway mucosa. A consequence of airway alcohol exchange is that EEAC is always less than AAC. In this study, we use a mathematical model of the human lung to determine the influence of subject lung size on the relative reduction of BrAC from AAC. We find that failure to inspire a full inspiration reduces the BrAC at full exhalation, but increases the BrAC at minimum exhalation. In addition, a reduced inhaled volume and can lead to an inability to provide an adequate breath volume. We conclude that alcohol exchange with the airways during the single exhalation
breath test is dependent on lung size of the
subject with a bias against subjects with smaller lung
size.

Keywords—Ethyl alcohol, Ethanol, Bronchial circulation,
Airway gas exchange.

INTRODUCTION

An assumption used in the development of the
alcohol breath test (ABT) is that the ethanol concentration
in the last part of the exhaled breath is equal to
that in the alveolar gas. This long-held assumption is
the basis for justifying the ABT1 as an accurate
measure of blood alcohol concentration (BAC).
However, under normal circumstances, a singleexhalation
alcohol breath test shows a gradually and
continually increasing breath alcohol concentration
(BrAC) if the subject exhales at a constant rate
(Fig. 1). The end-exhaled alcohol concentration
(EEAC) is always lower than the alveolar alcohol
concentration (AAC). As more volume is exhaled the
BrAC continues to increase. It has recently been shown
that EEAC is less than AAC due to the exchange of
alcohol in the airways during both inspiration and
expiration.2,3,8
Earlier studies have examined the assumption of
equality between end-exhaled and AAC by comparing
ABT values with blood measurements and found a
considerable amount of variation in the ratio of EEAC
to BAC. For further evidence regarding the lack of
end-exhaled and alveolar equality, two studies10,13
have shown that EEAC is approximately 15–20%
lower than AAC on average (obtained using isothermal
rebreathing). The explanation for this variation
has been discussed before.2,8 The physiological
importance of the discrepancy between EEAC and
AAC are the subject of this study.
Two recent studies have demonstrated a relationship
between the blood:breath2 ratio (BBR) for alcohol and
body weight14 or gender11 in normal subjects. Thus, it
may be possible that the BBR for alcohol is dependent
on physiological or anatomic differences among individual
subjects.9 One anatomical feature, lung size,
depends on body size, age, gender and ethnicity.
When an ABT is performed, subjects are not
required to control either the volume inhaled or the
Address correspondence to Michael P. Hlastala, Division of
Pulmonary and Critical Care Medicine, University of Washington,
Box 356522, Seattle, WA 98195-6522, USA. Electronic mail: hlastala@
u.washington.edu
1 A list of abbreviations used in this paper is shown in Table 1.
2 The blood:breath ratio is equal to the ratio of end-exhaled alcohol
concentration divided by blood alcohol concentration (EEAC/BAC).
Annals of Biomedical Engineering ( 2006)
DOI: 10.1007/s10439-006-9216-3
2006 Biomedical Engineering Society
volume exhaled. Under normal resting conditions, a
subject inhales and exhales a tidal volume (VT)
beginning from a functional residual capacity (FRC)
(Fig. 2). When administering an ABT, the subject is
asked to inhale ambient air and exhale into the breath
test instrument as far as possible. Although the subject
is asked to take a full inhalation, he/she is not required
to inhale to total lung capacity (TLC). Because it takes
some effort to inhale from FRC to TLC, a volume
known as inspiratory capacity (IC), it is most likely
that a subject’s lung size is less than TLC at the time
exhalation is initiated (gray line in Fig. 2). Some subjects
may exhale after inhaling only a very small volume.
The expiratory volume also varies naturally
between tests. To obtain a valid ABT, a subject can
exhale any amount between the minimum exhaled
volume required by the particular breath test instrument
(usually either 1.1 or 1.5 l)5 and the maximum
exhaled volume of the lungs, which is limited by the
vital capacity (VC), the difference between TLC and
residual volume (RV). The exhaled volume depends on
the mechanical limitations of the lungs and the relative
effort of the subject, which may vary from time to
time. For the calculations below, we assume that an
average exhaled volume is the average of the minimum
volume and the VC.
Lung volume varies substantially among individual
human subjects (both normal and with lung disease). In
1991, the American Thoracic Society (ATS) compiled
data from three international societies (the ATS, the
European Community for Coal and Steel, and the
European Society for Clinical Respiratory Research)
and published a summary document of lung volumes in
normal, non-smoking, human subjects for clinical use
in interpretation of pulmonary function tests.1 Collectively,
the summary of data (Table 2) shows that, in
adults, lung volumes increases with body height and
decreases with age. Lung volumes are smaller in African
Americans, both males and females, than their Caucasian
height-, age-, and gender- matched counterparts.
For either racial group, females have smaller vital
capacities than males. Because individuals with smaller
lung size must exhale a greater fraction of their lung
volume to fulfill any minimum volume requirement for
a valid sample, we reasoned that a subject with a smaller
lung volume would exhale farther along the increasing
exhaled partial pressure profile before an end-exhaled
sample is taken (see Fig. 3). Consequently, the alcohol
breath test would tend to overpredict the BAC for
individuals with small lung volumes.
We use a mathematical model2 to explore the
dependence of BrAC on lung size (a function of height,
age, gender, and race), inspiratory volume, and expiratory
volume. We hypothesize that BBR will depend
on the subject physical characteristics as well as the
level of cooperation.
FIGURE 2. Lung volume tracing for a single exhalation
maneuver. A subject breathes tidal volumes (VT) at functional
residual capacity (FRC) and then expands his lungs to total
lung capacity (TLC) by inhaling a volume equal to the inspiratory
capacity (IC). The subject exhales his vital capacity (VC)
at a constant flow rate, which causes his lung volume to
approach residual volume (RV). The gray tracing shows the
lung volume dimensions if the subject only inhales 50% of IC
during the prolonged inhalation.
BrAC
AAC
0.2
0.4
0.6
0.8
1.0
I
III
II
0 1 3 4 5
Exhaled Volume (Liters)
0.0
2
FIGURE 1. Exhaled ethanol concentration, normalized by
alveolar alcohol concentration, over a full exhalation at a
constant flow (From4).
TABLE 1. Glossary of abbreviations.
AAC Alveolar alcohol concentration
ABT Alcohol breath test
ATS American Thoracic Society
BAC Blood alcohol concentration
BBR Blood:breath ratio
BrAC Breath alcohol concentration
EEAC End-exhaled alcohol concentration
FRC Functional residual capacity
IC Inspiratory capacity
RR Respiratory rate
RV Residual volume
TLC Total lung capacity
VC Vital capacity
VI Volume of inspiration
VT Tidal volume
M.P. HLASTALA AND J.C. ANDERSON
METHODS
Mathematical Model
A detailed description of the model has been published
previously.2,4,15 Only the essential features will
be described here. The airway tree has a symmetric
bifurcating structure through 18 generations. The
respiratory bronchioles and alveoli are lumped
together into a single well-mixed alveolar unit. Axially,
the airways are divided into 480 control volumes.
TABLE 2. Predicted forced vital capacity for healthy, Non-smoking subjects: Caucasian and African American, male and female.
Predicted vital capacity (l)
Caucasian African-American
Height (in) Height (m) Age (Year) Male Female Male Female
51 1.30 20 2.587 2.137 2.866 2.244
51 1.30 40 2.195 1.721 2.430 1.810
51 1.30 60 1.803 1.305 1.994 1.376
55 1.40 20 3.178 2.560 3.191 2.541
55 1.40 40 2.786 2.144 2.755 2.107
55 1.40 60 2.394 1.728 2.319 1.673
59 1.50 20 3.770 2.984 3.517 2.838
59 1.50 40 3.378 2.568 3.081 2.404
59 1.50 60 2.986 2.152 2.645 1.970
63 1.60 20 4.361 3.407 3.842 3.135
63 1.60 40 3.969 2.991 3.406 2.701
63 1.60 60 3.577 2.575 2.970 2.267
67 1.70 20 4.952 3.830 4.167 3.432
67 1.70 40 4.560 3.414 3.731 2.998
67 1.70 60 4.168 2.998 3.295 2.564
71 1.80 20 5.544 4.254 4.493 3.729
71 1.80 40 5.152 3.838 4.057 3.295
71 1.80 60 4.760 3.422 3.621 2.861
75 1.90 20 6.135 4.677 4.818 4.026
75 1.90 40 5.743 4.261 4.382 3.592
75 1.90 60 5.351 3.845 3.946 3.158
79 2.00 20 6.727 5.100 5.144 4.323
79 2.00 40 6.335 4.684 4.708 3.889
79 2.00 60 5.943 4.268 4.272 3.455
FIGURE 3. Effect of lung size (as represented by vital capacity) on the exhalation profile. At a given exhaled volume (e.g., 1.5 l),
BrAC/AAC is inversely related to lung size. The model simulated a lung performing an IC inhalation (IC = 0.75 Æ VC) and a VC
exhalation at a rate of 200 ml s)1. The horizontal solid bars indicate the end-exhaled normalized BrAC at an average exhaled
volume. The relative average end-exhaled breath to alveolar concentration ratios are 0.767, 0.722 and 0.705 for subject vital
capacities of 2.0, 4.0, and 6.0 l, respectively.
Single-Exhalation Alcohol Breath Test
Radially, the airways are divided into six concentric
layers: (1) the airway lumen, (2) a thin mucous layer,
(3) connective tissue (epithelium and mucosal tissue),
(4) the bronchial circulation, (5) the adventitia, and (6)
the pulmonary circulation. Functionally, the upper
respiratory tract and cartilaginous airways (generation<
10) only have the first four layers. Within each
radial layer, concentration and temperature values are
bulk averages for the entire layer. Mass and energy are
transported between lumenal control volumes by bulk
convection and axial diffusion. Radial transport
between the gas phase and mucous layer is described
with heat and mass transfer coefficients. Radial
transport of water and soluble gas between concentric
layers occurs via filtration (from bronchial circulation
to mucus) and diffusion (Fick’s law). In the alveolar
unit, the concentration of soluble gas is allowed to vary
with time and depends on the pulmonary blood flow,
ventilation, blood solubility, and concentration of
soluble gas in the incoming blood as described by a
mass balance on the alveolar compartment.
Because airway volume increases with increasing
lung size, the lengths and diameter of the intraparenchymal
airways were scaled to ensure the ratio of the
airway volume to the VC was constant. Since the VC
of the Weibel lung model is 5000 ml, these dimensions
were scaled by the factor (VC/5000)1/3. None of
these airway dimensions changed dynamically during
the breathing cycle. The dimensions of the airway wall
compartments were calculated using data and a
method outlined previously.2
Mass and energy balances around a control volume
produce three partial-differential in time, t, and space,
z and nine ordinary differential equations. The equations
are solved simultaneously for the following 12
dependent variables: the mole fraction of soluble gas in
the air, mucous, connective tissue, bronchial bed, and
adventitial tissue layers; the temperature of the air,
mucous, connective tissue, bronchial bed, and adventitial
tissue layers; the mole fraction of water in the air;
and the mucous thickness. The 12 differential equations
are solved numerically using previously published
boundary conditions.2 The spatial derivatives are
approximated by upwind finite difference while the
time derivatives are solved using LSODE, an integrating
software package developed by Hindmarsh.7
Computer Simulations
Before an ABT was simulated, the model first must
reach breath-to-breath steady-state conditions. The
temperature, water concentrations, and ethanol concentrations
within the mathematical model were
brought to steady-state conditions by simulating tidal
breathing at FRC. A respiratory rate of 12 br min)1, a
sinusoidal flow waveform, and a tidal volume equal to
10% of VC were used for the case study (Table 2). For
the parameter study, tidal volume was varied between
200 and 600 ml in 100 ml increments. The inspired air
temperature and relative humidity were set to 23C
and 50%, respectively. The bronchial blood flow rate
was set to 1 ml s)1. The concentration of ethanol in the
pulmonary arterial blood was constant and equal to
0.10 g dl)1 of blood. Steady-state conditions were
reached when the end-exhaled water and ethanol
concentrations changed by less than 0.1% between
breaths. Then, the model simulated a single inhalation
of a volume equal to or a fraction of IC, the volume
from FRC to TLC, at a constant rate of 1500 ml s)1.
Inspiratory capacity was approximated to be 75% of
the VC.6 Then, the model simulated a prolonged
exhalation; the lung was emptied at a rate of
200 ml s)1 until the lung volume reached RV.
RESULTS
For highly soluble gas like ethyl alcohol, exhaled
concentration continues to increase with continued
exhalation due to airway gas exchange. An example of
an exhaled ethyl alcohol profile is shown in Fig. 1. In
this example, a male subject with a BAC 0.09 g/dl
inhaled quickly to TLC, exhaled at a constant flow
rate, and stopped exhalation at RV.4 Several different
expiratory profiles for the same subject are shown.
During exhalation at a constant exhaled flow rate, the
exhaled ethanol concentration rises continuously during
the final phase (phase III) of the ethanol profile.
When the subject stops exhalation (either due to
reaching RV or simply because the subject chooses to
stop), the alcohol concentration plotted against time
levels off because exhalation has stopped and no new
air enters the breath test machine.8 At this time, a
sample is taken and assumed to be ‘‘alveolar’’ in nature.
However, any breath sample is ‘‘always’’ lower in
alcohol concentration than AAC. The classical interpretation
assumes that the EEAC is related to the BAC
with an average BBR of 2100. This factor neglects the
exchange of alcohol with the airways of the lungs and
any variability in this ratio among individuals.
From the model’s predictions of exhaled ethanol
profiles from human subjects,4 we can describe the
mechanisms underlying ethanol exchange in the airways.
As fresh air is inhaled, it absorbs ethanol from
the mucous layer, thereby depleting the ethanol concentration
in the airway wall. Because of the small
bronchial blood flow (Qbr) and the significant diffusion
barrier between the bronchial circulation and mucous
layer, the mucus is not replenished with ethanol before
M.P. HLASTALA AND J.C. ANDERSON
exhalation begins. During exhalation, respired air
encounters a lower concentration of ethanol in the
mucus and, therefore, a large driving force for the
deposition of ethanol onto the mucus. This large airto-
mucus gradient promotes recovery of ethanol by the
mucous layer, decreases the ethanol concentration in
the air, and delays the rise in ethanol concentration at
the mouth. A large (small) air-to-mucus gradient causes
a slowly (rapidly) increasing phase III slope. These
absorption–desorption phenomena decrease the ethanol
concentration leaving the lung (relative to the
alveolar concentration) throughout exhalation and
are the major mechanisms of pulmonary ethanol
exchange.
The mathematical model simulated the effect of lung
size on the exhalation profile (Fig. 3). After a steadystate
was reached during tidal breathing (RR = 12 br
min)1 and VT = 400 ml), the model simulated a full
inhalation from FRC to TLC and then a constant
(200 ml s)1) exhalation to RV. These conditions were
simulated in five lung sizes as represented by the VC
that varied from 2 l to 6 l. The normalized BrAC after
a maximum exhalation (to RV) was 0.79 for all five
lung sizes and appears to be unaffected by lung size
(i.e., VC). However, many times subjects do not exhale
their entire VC and, in addition, most alcohol breathtesting
instruments only require a minimum exhaled
volume (e.g., 1.5 l) before a breath test is acceptable.
We examined the normalized BrAC in Fig. 3 after 1.5 l
of air had been exhaled from lungs of different sizes:
small (VC = 2 l), medium (VC = 4 l) and large
(VC = 6 l). The normalized BrAC was 0.74, 0.61, and
0.55, respectively. At this exhaled volume, the ratio of
change in normalized BrAC to change in lung size is
)0.048 l)1. Additionally, we examined how lung size
affected the normalized BrAC (Fig. 3) after an average
exhalation. We assumed that, on average, an individual
would exhale a volume that is the mean of the
minimum (1.5 l) and maximum (VC) volume. Thus,
for an individual with VC = 6 l, an average exhaled
volume (after an IC inhalation) is 3.75 l and results in a
normalized BrAC of 0.705. Subjects with smaller lung
size, 4 and 2 l, and providing an average exhalation
have normalized BrAC of 0.722 and 0.767, respectively.
For an average exhalation, individuals with
smaller lung size provide BrAC samples that are
greater than those with larger lung size because of the
minimum exhalation volume requirement in combination
with the mechanics of airway gas exchange. The
effect of lung size on this average BrAC is )0.015 l)1.
Thus, a one liter increase in VC decreases the normalized
BrAC at this average volume by 0.015.
The minimum, average, and maximum BrAC values
for subjects with different vital capacities are shown in
Fig. 4. Results are shown for vital capacities varying
between 2.0 and 7.0 l and for an inspiration of a full
IC. As lung VC increases, the average BrAC decreases.
For lungs with vital capacities less than 2.0 l, it is often
difficult for the subject to fulfill the mininum 1.5 l
minimum exhalation volume.
We simulated the effect of inspiratory volume on the
exhalation profile for a given lung size (Fig. 5). Once a
periodic steady-state was achieved (VT = 400 ml), the
model simulated an inhalation from FRC. The inhaled
volume depended on the simulation. For a maximum
IC inhalation, the inhaled volume was assumed to be
0.75ÆVC. Smaller inhaled volumes of 66%, 33%, and
10% of IC were simulated. After inhalation, a constant
(200 ml s)1) exhalation to RV was simulated. Figure 5
shows the effect of inhaled volume on normalized
BrAC from three lungs of varying size, VC = 2 l
(panel A), 4 l (panel B) and 6 l (panel C). For every VC
studied, a decrease in inhaled volume causes: (1) an
increase in normalized BrAC at a given exhaled volume;
(2) an increase in the normalized BrAC from a
minimum (1.5 l) and average exhalation; and (3) a
decrease in the normalized BrAC after a maximum
exhalation to RV. Specifically, a decrease in inspired
volume in a lung with VC = 4 l causes the normalized
BrAC after a minimum exhalation to increase by
0.048 l)1, the normalized BrAC after an average
exhalation to increase 0.004 l)1, and the normalized
BrAC after a maximum exhalation to decrease
0.022 l)1. These rates of change of normalized BrAC
per inspired volume are a function of VC. A two liter
increase (decrease) in VC causes these rates to decrease
(increase) by 15%. As compared with individuals with
small VC, subjects with large VC can choose from
more possible inspired volumes that will result in a
minimum exhaled volume and an acceptable breath
test. We examined the effect of tidal volume on BrAC
and found that a 100 ml increase in tidal volume
FIGURE 4. The relationship between normalized breath
alcohol concentration and lung size (based on vital capacity)
are shown for IC inhalations followed by different exhaled
volumes: maximum (VC), average and minimum (1.5 l). See
text for definitions.
Single-Exhalation Alcohol Breath Test
decreased all three measures (minimum, average, and
maximum exhalation) of normalized BrAC by 0.01.
The variation of lung volume among individuals of
differing gender, body height and age are shown in
Table 2. Typical values are presented in Table 2 for
normal Caucasian and African American male and
female adults. Lung volumes are greater in equally sized
and aged males compared with females, in Caucasians
FIGURE 5. Effect of inspiratory volume on the exhalation profile for a given lung size. At a given exhaled volume (e.g., 1.5 l),
BrAC/AAC is inversely related to volume of gas inhaled (VI). The model simulated a lung inhaling a volume, VI, from FRC and
exhaling to RV at a rate of 200 ml s)1. VC represents lung size. For each panel, VC is 2 l (panel A), 4 l (panel B), and 6 l (panel C).
M.P. HLASTALA AND J.C. ANDERSON
compared with African Americans and in younger
adults compared with older adults. Table 3 shows the
predicted BrAC normalized by AAC taken from Fig. 4.
The predictions of the mathematical model show a
greater BrAC (relative to AAC) in all cases comparing a
smaller lung volume with a larger lung volume.
DISCUSSION
Alcohol breath testing-instruments require a minimum
exhaled volume before a breath sample is taken
at the end of an exhalation. For a subject with a small
lung size, a greater fraction of the VC must be exhaled
before the sample criteria are fulfilled. Most breath test
instruments require a minimum exhalation pressure (or
flow) for a minimal duration of time (4–6 s and a
minimal exhalation volume (between 1.1 l and 1.5 l).
For our calculations, we chose 1.5 l as the minimum
exhaled volume. Once the minimum criteria are fulfilled,
a sample will be taken when the change in
exhaled alcohol partial pressure levels off (always
achievable when the exhaled flow is stopped). For a
subject with a VC of 6 l using a BAC Verifier Datamaster
(minimum volume is 1.5 l), a sample can be
obtained any where between 1.5 and 6.0 l of exhalation
because the subject may choose to stop exhalation any
where between 1.5 l and VC. For a subject with a VC
of 2 l, a sample can be obtained using a BAC Verifier
Datamaster anywhere between 1.5 and 2.0 l of exhalation.
A subject with a small lung size will proceed
further up the increasing BrAC exhaled profile before a
sample is taken (Fig. 3).
One of the fundamental assumptions of the ABT is
that during exhalation, the BrAC continues to increase
until alveolar air reaches the mouth. At this point the
BrAC levels off. This observation has been assumed to
indicate that EEAC is equal to AAC. However, breath
alcohol always increases during exhalation as air
moves out of the mouth,4 never reaching AAC. The
flatness of the slope of the exhaled alcohol profile
simply means that exhalation has stopped. It is not an
indication of alveolar air. Additional support of this
idea follows from two studies using isothermal rebreathing
in human subjects,10,13 which showed that
EEAC (with a single-exhalation maneuver) is always
less than AAC. The difference, on average, is
approximately 15%8 and consistent with the ideas
described in this paper. Individuals with smaller lung
size are predicted to have a smaller difference between
EEAC and AAC such that an individual with a smaller
lung size, would have an ABT that is greater than an
individual with a larger lung size.
The major thesis of this paper is that lung size and
breathing pattern influence the BrAC reading determined
with a breath-testing instrument. Figure 3
shows exhaled alcohol profiles for subjects taking a full
inspiration followed by a full expiration. For each lung
size (represented by VC), the end exhaled BrAC is the
same. In other words, if a subject takes a full inspiration
followed by a full exhalation, there would be no
size dependence. If these subjects were to exhale just to
the minimum volume requirement (1.5 l), the greatest
discrepancy is predicted between subjects with differing
lung size. Every thing else being equal (including
BAC), the subject with the smallest lung size would
TABLE 3. Relative BrAC comparisons.
Predicted VC (l) BrAC/AAC
Min Avg Max
55’’ vs. 75’’ – Male 40 Years
55’’ Male – 40 Years 2.786 0.681 0.747 0.794
75’’ Male – 40 Years 5.743 0.509 0.675 0.770
BrAC Ratio of small to large volume 1.34 1.11 1.03
67’’ Female vs. 67’’ Male – 40 Years
67’’ Female – 40 Years 3.414 0.629 0.723 0.785
67’’ Male – 40 Years 4.560 0.560 0.696 0.776
BrAC Ratio of small to large volume 1.12 1.04 1.01
67’’ AA Male vs. 67’’ Caucasian Male – 40 Years
67’’ AA Male – 40 Years 3.731 0.607 0.714 0.782
67’’ Caucasian Male – 40 Years 4.560 0.560 0.696 0.776
BrAC Ratio of small to large volume 1.08 1.03 1.01
75’’ Male – 60 Years vs. 20 Years
75’’ Male – 60 Years 5.544 0.516 0.678 0.771
75’’ Male – 20 Years 6.351 0.487 0.667 0.767
BrAC Ratio of small to large volume 1.06 1.02 1.00
Single-Exhalation Alcohol Breath Test
have the greatest BrAC. Table 3 summarizes this effect
by comparing the relative ratio of BrAC between two
hypothetical subjects that differ in height, gender, race,
or age. Comparing a male and female of the same
height, the female has a minimum exhalation BrAC
that is approximately 12% greater than the male.
Comparing a 55-inch tall male with a 75-inch tall male,
at minimum exhalation, the smaller male has a 34%
greater BrAC than the taller male. With a minimum
exhalation, the overestimate for the smaller lung individual
is substantial.
On the average, a subject with a valid breath test can
exhale to any point between the minimum volume and
the maximum exhalation. When the subject stops
exhaling, new breath is no longer being delivered for
analysis. Therefore, the BrAC levels off when plotted
against time. An average of the different exhalation
volumes would be approximately equal to the mean of
the volumes exhaled at 1.5 l and the maximum exhalation.
For hypothetical subjects that differ in either
their height, gender, race or age, the ratios of average
BrAC between matched subjects are shown in Column
4 of Table 3. Comparing a 67-inch tall 40-year-old
male and with a female of the same height and age, the
female has an average exhaled BrAC that is approximately
4% greater than the male. Comparing a 55-inch
tall 40-year-old male with a 75-inch tall 40-year-old
male, at average exhalation, the smaller male has an
11% greater BrAC than the taller male. Comparing a
67-inch tall 40-year-old African American male with a
67-inch tall 40-year-old Caucasian male, at average
exhalation, the African American male has a 3%
greater BrAC than the Caucasian male. Comparing a
75-inch tall 20-year-old Caucasian male with a 75-inch
tall 60-year-old Caucasian male, at average exhalation,
the African American male has a 2% greater BrAC
than the Caucasian male. With an average exhalation,
the bias for the smaller lung individual is less than the
bias predicted for the minimum exhalation. The largest
discrepancy is related to body height because of the
greatest difference in relative lung size.
The mechanism of airway gas exchange has been
described briefly above and used to explain how ethanol
exchanges in the lung.2–4 Based on this mechanism
of ethanol exchange, the effect of changes in
inspired volume on BrAC can be understood. A small
inhaled volume will reduce the ethanol concentration
in the airway mucus and tissue layers to a lesser extent
than a large inhaled volume. During exhalation, the
former case will have a smaller air-to-mucus gradient
than the latter case. A smaller gradient causes less
ethanol to be deposited to the airway surface and, as a
result, the BrAC rises more rapidly when the inhaled
volume is small than when it is large (Fig. 5). The
maximum BrAC/AAC depends on the ratio of inspiratory-
to-expiratory time, but because the flow rates
are prescribed, inhaled volumes are defined by percent
of VC and exhalation always proceeds to RV, the
maximum BrAC/AAC only depends on inhaled volume
(VI) as shown in Fig. 5.
The ability to fulfill the minimum exhalation criteria
for a breath test instrument is limited by individuals
with smaller lungs and less than full inhalations. Figure
5 illustrates the combined impact lung size and
inspiratory volume have on the ability to provide a
minimum sample volume. As the size of the individual’s
lungs decrease, it becomes more important to
inspire a greater volume before exhalation. This finding
is consistent with the observations of Jones and
Andersson12 showing the probability of failing to
provide a minimum sample is greater in females than
males. Both genders show an increased in the probability
of an insufficient sample with increasing age.
There are two recent studies that can be used to
compare with our model predictions. Ska˚ le et al.14 and
Jones and Andersson11 determined the blood–breath
ratio (or partition ratio) for several subjects (male and
female) with varying heights, ages and body weight.
Jones studied 9 male and 9 female subjects and found
average BBRs of 2553±576 for males and 2417±494
for females. Although not statistically significant, the
trend agrees with our predictions. The ratio of females
to males is 1.056. The smaller lung size females had a
5.6% greater BrAC than the males. Ska˚ le et al. studied
9 male and 15 female subjects and found that the
blood–breath ratio was dependent on body weight.
The average BBR for subjects with body weights of
50–70 kg was approximately 2250 while the BBR for
subjects with body weights of 90–100 kg was approximately
2476. The ratio is 1.10. The BrAC for the
smaller subjects was 10% greater than the larger
subjects. Neither of these two papers measured lung
VC as this was not part of their hypotheses. So we
cannot directly compare our data. However the trends
are consistent with the hypothesis put forward in this
paper that individuals with smaller lung size have
greater BrAC in comparison to the BAC3 .
The present hypothesis is consistent with published
data and with the mechanisms of pulmonary gas exchange.
We encourage future investigators to include
3 The Blood–Breath Ratio (BBR) is a commonly used term in
forensic science. Because alcohol is a very highly soluble gas, the
ratio of concentration in the blood normalized by that in the breath
is a very large number (typically around 2000). For a given Blood
Alcohol Concentration (BAC), the Breath Alcohol Concentration
(BrAC) is about 1/2000 x BAC. With smaller lung volumes, the
BrAC is greater, hence the BBR (= BAC/BrAC) is lesser. In one
case the BrAC is in the numerator (BrAC/AAC). In the other case,
the BrAC is in the denominator. So a greater BBR is the same as a
lesser BrAC/AAC.
M.P. HLASTALA AND J.C. ANDERSON
the measurement of lung VC with the measurements
of BBR in order to provide data to test our
hypothesis. Surely, if there is anatomically dependent
variation in the alcohol breath test, it is important to
make corrections for the bias of the test. Once these
data are obtained, several possible alternative solutions
can be used: appropriate corrections to the
BrAC values can be made; adjustable legal limits can
be used for individuals of differing lung size; or rebreathing
can be used to obtain a better sample of
AAC.
In conclusion, alcohol exchanges between the respired
air and the airway tissue during both inspiration
and expiration. This airway gas exchange causes the
exhaled alcohol concentration to always be less than
the AAC. A consequence of this airway exchange is
that BrAC depends on lung size and the amount of
effort provided by the subject.
ACKNOWLEDGMENTS
This work was supported, in part, by National
Institute for Biomedical Imaging and Bioengineering
Grant T32 EB001650 and by National Heart, Lung,
and Blood Institute Grants HL24163 and HL073598.
REFERENCES
1American Thoracic Society. Lung function testing: Selection
of reference values and interpretative strategies. Am.
Rev. Respir. Dis. 144:1202–1218, 1991.
2Anderson, J. C., A. L. Babb, and M. P. Hlastala. Modeling
soluble gas exchange in the airways and alveoli. Ann.
Biomed. Eng. 31:1402–1422, 2003.
3Anderson, J. C. and M. P. Hlastala. Breath tests and airway
gas exchange. Pulm. Pharmacol. Ther. in press, 2006.
4George, S. C., A. L. Babb, and M. P. Hlastala. Dynamics
of soluble gas exchange in the airways. III. Single-exhalation
breathing maneuver. J. Appl. Physiol. 75:2439–2449,
1993.
5Harding, P. Methods for breath analysis. In: Medical–Legal
Aspects of Alcohol (4th ed.), edited by Garriott J. C.
Tucson: Lawyers & Judges Publishing Co., 2003, pp. 185–
211.
6Hildebrandt, J. Structural and mechanical aspects of respiration.
In: Textbook of physiology, edited by Patton H.
D., Fuchs A. F., Hille B., Scher A. M., and Steiner R.
Philadelphia: W.B. Saunders Co., 1989, pp. 991–1011.
7Hindmarsh, A. LSODE (computer software). Laurence
Livermore Laboratory, Livermore, CA.
8Hlastala, M. P. The alcohol breath test – a review. J. Appl.
Physiol. 84:401–408, 1998.
9Hlastala, M. P. Invited editorial on ‘‘the alcohol breath
test’’. J. Appl. Physiol. 93:405–406, 2002.
10Jones, A. W. Role of rebreathing in determination of the
blood–breath ratio of expired ethanol. J. Appl. Physiol.
55:1237–1241, 1983.
11Jones, A. W. and L. Andersson. Comparison of ethanol
concentrations in venous blood and end-expired breath
during a controlled drinking study. Forensic Sci. Int.
132:18–25, 2003.
12Jones, A. W. and L. Andersson. Variability of the blood/
breath alcohol ratio in drinking drivers. J. Forensic. Sci.
41:916–921, 1996.
13Ohlsson, J., D. D. Ralph, M. A. Mandelkorn, A. L. Babb,
and M. P. Hlastala. Accurate measurement of blood alcohol
concentration with isothermal rebreathing. J. Stud.
Alcohol 51:6–13, 1990.
14Ska˚ le, A. G., L. Slørdal, G. Wethe, and J. Mørland. Blood/
breath ratio at low alcohol levels: A controlled study. Ann.
Toxicol. Analytique. XIV:41.
15Tsu, M. E., A. L. Babb, D. D. Ralph, and M. P. Hlastala.
Dynamics of heat, water, and soluble gas exchange in the
human airways: 1. A model study. Ann. Biomed. Eng.
16:547–571, 1988.

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DUI LIES

January 10, 2007 by alabamadui

DUI LIES

Many people, attorneys and judges included, have a completely wrong attitude towards a Alabama DUI charge. They are trapped by believing many common LIES about an Alabama DUI. Such LIES can lead to malpractice by the attorney and to dire consequences for the client who suffers due to the lawyer’s lack of knowledge. The LIES surrounding DUI are:

LIE 1: A DUI is a “Simple” charge

Let me ask: D you think it is ‘simple’ to loose your job?

Is it simple to be unable to drive?

Is it ‘simple’ to be able to travel to other countries?

Is it ‘simple’ to be unable to rent an apartment?

Is it ‘simple’ to be banned for life from having a Commercial driver’s license?

Is it ‘simple’ to go to jail?

Is damaged credit rating ‘simple’?

Is it simple for your insurance to increase by thousands of dollars for yeas to come?

This is just the start of some of the hidden costs of a DUI. This is a charge that keeps on giving-it follows you for years, possibly even lifetime. There is nothing ‘simple’ about these types of penalties you can suffer form a ‘simple’ DUI.

Regretfully, far to many untrained attorneys think of DUI’s as ‘simple and advise their clients to quickly enter a plea. A trained, competent DUI Lawyer can help you understand the dangers you face and protect you from this harm.

LIE 2: A DUI case is the same as any other Criminal Case

If the consequences were not so serious, this LIE would be humorous. Recently a judge said ‘A DUI case is one of the most difficult cases to try, more difficult than most murder cases.” In many areas, the courts handle DUI cases differently from other offenses. For example, in a murder case, the defense lawyer will order an independent analysis of ballistics tests, blood splatter patterns, fingerprints, and other physical evidence. This is not true in drunk driving cases. Alabama does not require an officer taking a breath test to capture some of the breath so it can be analyzed independently at a later date, even though the machines can seal samples at a minimal cost. The U.S. Supreme Court has said that it is perfectly acceptable that such critical evidence is destroyed.

In the judicial system DUI’s are ‘special’. Special? Yes, different rules apply to a DUI case. In a run of the mill criminal case-murder, drugs, etc. – you would be allowed to view and test the evidence against you. If blood were involved you could have it tested also. In most DUI’s the evidence consist of a breath test which produces a number printed on a piece of paper. In Alabama your breath is not saved for additional testing. The machine- Draeger Alcotest 7110- is fully capable of saving a sample (it cost about $1.50) but the state has chosen not to do so. The courts say, no big deal, it is DUI evidence and we will ignore that evidence was destroyed.

Attorneys who are not heavily trained in DUI defense or even more disturbing, the ones who just want to earn a quick buck do not know how to protect their clients. The attorney could face malpractice from mishandling such cases but even more disturbing—the client is the one who will suffer for years to come.

LIE 3: If you were arrested, you must be guilty

You certainly don’t what an attorney representing you who starts off thinking you are guilty. An attorney should believe in his client and devote himself to defending his client.

This is perhaps the most troubling LIE because so many attorneys and individuals believe it. Since this mindset can eliminate objectivity, an attorney who believes this has no business representing a person accused of drunk driving.

The evidence in most drunk driving cases is a breath test, not a blood test. A skillful attorney can be successful in exposing the problems with such a test. Because of their lack of sophistication, most scientists would not trust the results of a breath test machine as a basis for research or investigation. Both the accuracy and reliability of these machines are subject to challenge.

The breath machine is just that—the low bid machine purchase in a government contract. There are a number of ways to attack a machine test. This is not a scientific instrument yet the state wants to treat it as such. There are reliability, accuracy, administration and training errors, just to name a few.

It takes extensive training and study by an attorney to challenge these test. Attempting to defend a DUI case without this training and knowledge could expose the attorney to a malpractice charge and leave the defendant to suffer the consequences.

LIE 4: You can’t win an Alabama DUI case.

Oh my goodness, we have allowed ourselves to be brainwashed into believing this lie. It is outrageous to think that a person would actually pay a lawyer who believes this lie.

An experience DUI lawyer will start preparing for trial from the very first meeting. He will investigate and subpoena every piece of evidence available. The lawyer will often fight extensively through motions and other procedural maneuvers. The client should not automatically be advised to plead guilty because an attorney who is not properly trained believes that these cases are difficult or impossible to win.
Many lawyers will push a guilty plea without having done any investigation of the case. Possibly the client told the attorney he could not afford to fight the case.This is common but –did the attorney tell the client the hidden and long-term cost of a conviction and did the attorney explain the defense to the charge so the client could make an informed, intelligent decision?

Many times the client will realize the long-term cost of accepting a quick guilty plea is greater that the cost of fighting—that is if the options are fully explained by a competent attorney.

LIE 5: DUI is a Minor Offense

The stigma of a conviction can cause tremendous stress and fear. Many drivers whose licenses are suspended continue driving to keep a job and provide for their families. By doing so, they live in fear of being stopped, caught, and jailed for driving with a suspended license. Most of those convicted also suffer financially and socially. In most states, a DUI conviction is permanently on a driving record. Only those justly convicted should have to endure these emotional, financial, and psychological hardships.

It is not a crime to have a drink and drive. Convictions for drunk driving should only occur when a person’s blood alcohol level exceeds the arbitrary numerical standard set by the state, or when it is proven that a person’s bad driving is connected to an impaired state due to a high blood alcohol level.

Attorneys who improperly advise a client to plead guilty may be committing malpractice and open themselves to litigation for substandard representation. Usually, the driver’s do not know if they have been properly represented or of the state’s case was valid and based on a legal stop. A qualified DUI attorney is needed to investigate the case thoroughly and recommend the best alternative.

You have a right to inquire about the training your potential attorney has received. You should be sure that the lawyer has spent substantial time training specifically in the field of DUI.

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Physiological Responses to Ethanol

January 9, 2007 by alabamadui

Physiological Responses To Ethanol

Blood Alcohol Category of Dose Response Relationship for
Concentration Influence the Non-Habituated Consumer

0.01%-0.04 SUBACUT Social/Emotional: No behavioral changes
apparent to the casual observer. Influence negligible.
Cognitive: Shared Attention deficits detectable in sensitive individuals.
Memory: Unaffected
Fine Motor Abilities: Slight changes detectable by specialized tests.
Balance: Normal
Depressant Effect: Very Slight
Vision: Normal

0.03%-.12 EUPHORIA Social/Emotional: Mild state of euphoria;
increase in self-confidence and a decline in inhibitions; increase in sociability and gregariousness; decline in judgment and ability to comply with social controls.
Cognitive: Decline in information processing ability. Decreased attention.
Memory: Long-term memory basically unaffected. Short-term memory deficits apparent at 0.07% and above.
Orientation: Slightly narrowed.
Fine Motor Abilities: Sensory motor impairment begins. Information processing slowed resulting in a decline in performance on specialized tests
Balance: Baseline coordination deficits apparent on certain balance and coordination tasks.
Depressant Effect: Slight
Vision: Pursuit tracking significantly affected above 0.06%. Pendular nystagmus consistently present above 0.05%.

0.09%-.20 INTOXICATED Social/Emotional: Emotional
instability with a loss of critical judgment. Behavior manifested that is uncharacteristic of the subject in the sober state.
Cognitive: Impairment of perception and comprehension.
Memory: Declines evidence in both long and short term abilities.
Orientation: Loss of social awareness
Fine Motor Abilities: Gross deterioration.
Balance: Coordination grossly affected and inability to maintain balance evidence. Sensory motor incoordination.
Depressant Effect: Drowsiness
Vision: Reduced visual acuity with decrease in peripheral vision and glare recovery. Flicker fusion consistently appears.

0.18% – 0.30% CONFUSION Social/Emotional: Mental confusion.
Exaggerated emotional statres (fear, rage, sorrow).
Cognitive: Inncoherence
Memory: Continuing decline in ability to recollect past and present events.
Orientation: Disorientation
Fine Motor Abilities: Only slightly functional
Balance: staggering gait, increasing muscular incoordination with corresponding increased pain threshold.
Depressant Effect: Apathy and lethargy.
Vision: Diplopia (double vision). Disturbances of perception, color, form, motion & dimensions.

0.25% to 0.40% STUPOR Social/Emotional: Complete loss of social
awareness. General inertia.
Cognitive: Marked decreased response to stimuli.
Memory: Unreliable.
Orientation: Non-existent
Fine Motor Abilities: Lost
Balance: Inability to stand and marked muscular in coordination.
Depressant Effect: Impaired consciousness, sleep.
Vision: Only slightly functional and very blurred.

0.35% – 0.50% COMA Social/Emotional: Unconsciousness.
Cognitive: Coma
Orientation: Life threatening state. Abolished reflexes with incontinence of urine and feces.
Fine Motor Abilities: Anesthesia state with depressed or abolished reflexes.
Depressant Effect: Anesthesia state. Impairment of circulation and respiration. Subnormal temperature. Death possible.
Vision: Non-functional.
0.45 + DEATH Death from respiratory arrest can occur.
Dubowski, Kurt M. “Stages of Acute Alcohol Influence/Intoxication,” University of Oklahoma College of Medicine, 1985; Giguire, Williams E., “The Quantitative Measurement of Driving Impairment in the Field, “ Tenth International Conference of Alcohol, Drugs and Traffic Safety, Amsterdam, The Netherlands, 1986.

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Constitutional Rights Suspended in DUI Prosecution

January 9, 2007 by alabamadui

Constitutional DUI Limitations

YOUR CONSTITUTIONAL RIGHTS DO NOT APPLY FOR A DUI
Our Declaration of Independence begins “We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness.”
Our Constitution does not reserve or limit any of our rights due to a specific criminal charge. That means that someone accused of murder is entitled to the same rights as someone accused of writing a bad check. These rights apply to YOU as a citizen, not to a specific charge. This is the way it is ‘supposed to be’, but in the real world, IT IS NOT TRUE.
Our courts have continuously found ways to limit the Constitution and limit the rights of the people accused of DUI. You will find the follwing statments difficut to belive, but they are true:

If you are arrested for DUI, the officer will IMMEDIATELY seize your driver’s license and will not return it. This is a form of punishment and you have not even had an opportunity to talk with a lawyer, see a judge or post bail. You ARE PRESUMED GUILTY when our Constitution guarantees that you are to be presumed innocent unless proven otherwise – A DUI LIMITATION.

If you are arrested, the Officer will rarely read your Miranda rights to you even though he will continue to question you. You have watched TV and know this is wrong—Not for DUI’s. The court again has found A DUI LIMITATION.

If you are arrested and taken to jail for DUI, you should feel confident that you will be allowed to talk with an attorney prior to questioning or being asked to give incriminating evidence against yourself. This is true in all crimes except DUI, again – A DUI LIMITATION.

If you are arrested and refuse to take a breath test, our state law says that refusal can be admitted to a jury and a presumption of guilt attached. But— What about the 5th Amendment saying I have the right to remain silent and it cannot be used against me? – A DUI LIMITATION.

If you are driving and are stopped at a roadblock, then questioned about drinking- you easily think “wait, you have to have a reason to stop me, this is not legal”. This would be true if they were looking for drugs, or any other crime, but if it is a DUI stop — A DUI LIMITATION.

In most cases, if the government knowingly destroys evidence, that evidence cannot be used against you. In a DUI case, you are asked to take a breath test. The machine is capable of preserving the sample of your breath for additional testing. The Government, for monetary reasons and knowing there will be no punishment for destroying that evidence, has chosen not to maintain the sample, yet they are allowed to introduce their evidence — A DUI LIMITATION.

If you have a couple of quick drinks and are stopped within 5-10 minutes of leaving your house or a meeting, you may not be affected by the alcohol yet—still you will be requested to take a breath test and as long as it is taken within 2 hours of your arrest, that is close enough for Government work. It can be used against you and show you with a much higher alcohol level than what you had while you were actually driving. In effect you will be guilty of being capable of committiing a crime even though you were not intoxicated when stopped — A DUI LIMITATION.

A man’s home is his castle! We have heard this many times and you know the Constitution says the government must have a search warrant to enter your home, even for a murder investigation. A recent California case allowed the police to enter a home for a misdmeanor DUI investigation without a warrant. This was based on a neighbors tip; that is the police did not even see the person driving, they just entered the home without a warant. Surely this would not be allowed. Sorry — A DUI LIMITATION.

The constituion requires a warrant before evidence can be forcefully taken. In a nearby state, if you are stopped, asked to submit to a breath test and refuse (remember the 5th amendment and your right not to incriminate yourself)—A’Batmobile’ will be called to the scene, you will be strapped down and a police officer will take your blood on the spot. Yes, this is happening in Amercia because we have another — DUI LIMITATION.

You can be convicted of DUI even if your driving was not impaired. The law has what we call a ‘per se’ provision. That means if the machine says you are .08 or more, you are presumed guilty even if your driving was not affected. The government will not have to show your driving was impaired, just that a machine gave a certain number. You just thought you had a right to be presumed INNOCENT — A DUI LIMITATION.

The Constitution guarantees an accused the right to face their accuser in court before a jury. This is the Right of Confrontation. In DUI cases, the accuser is most often a machine that makes mathematical conversions to reach a number. This mathematical conversion is secret because the manufacturer considers it‘proprietary’. Math is generally considered to be an absolute and no one owns it, but in DUI cases you will not know the method used to compute your number because it is proprietary to the manufacturer. — A DUI LIMITATION.

Actual innocence is “irrelevant”. In August 2006 the Michigan Supreme Court said actual innocence of ‘impaired’ driving was IRRELEVANT! You read that correctly…. actual innocence of ‘impaired’ driving was IRRELEVANT! The Court convicted the defendants even though the court acknowledged the drivers were not impaired. They had apparently ingested marijuana at some point in the prior 3-4 weeks. The testimony was clear and the Court accepted the fact that they were not under the influence of the substance at the time they were driving. Still, they were convicted of DUI.— A DUI LIMITATION.

You get the idea. DUI has become a social crime and no politician will speak against the charges or means of applying penalties if they wish to remain in office. We also continue to move away from the problem—intoxicated drivers. The limits are lower and you can be convicted for a number that has no realtionship to your driving abilites. None of this addresses the repeat offenders who are heavily intoxicated but is does move towards a new form of prohibition in our country. One state has lowered the number to .04 for repeat offenders and it is easy to invision a nationwide move to lower the number to .04 for all drivers. In addition, DUI’s are the ‘cash cow’ for our court system. Court cost for a first time DUI are higher than for a felony drug possession. There are numerous reasons your case is being placed on a ‘fast track’. There are many powereful forces striving to increase the number of DUI convictions throughout our nation — all the more reason you need an experienced ALABAMA DUI ATTORNEY.

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BREATH ALCOHOL MEASUREMENT

January 8, 2007 by alabamadui

ALCOHOL AND BREATH ALCOHOL MEASUREMENT

There are two means of electronically measuring the breath alcohol concentration. One method is by using an infrared and the other method is a fuel cell.

Infrared Cell

Alcohol strongly absorbs infrared energy at mainly two wavelengths namely 3,4 microns and 9,5 microns. 9,5 microns is referred to as the primary wavelength in the measurement of ethyl alcohol, or ethanol, the alcohol that is present in alcoholic beverages. Other substances absorb infrared energy at 3,4 microns therefore absorption at 9,5 microns, the primary wavelength, is used to determine alcohol concentration. In the infrared cell used to measure the alcohol concentration an infrared beam is passed through the breath/alcohol mixture and detected by an infrared detector. The greater the concentration of alcohol in the breath sample the greater the amount of infrared light that is absorbed (Lambert-Beer)

The process of analysis of a breath sample for alcohol by infrared cell as follows:

1. The breath sample is captured in the infra-red cell

2. Infrared energy from the source passes through the breath sample. The alcohol in the breath sample absorbs some of the infrared energy.

3. The energy absorbed is related to the amount of alcohol present.

4. The reduction of infrared energy is detected and measured by the infrared detector the amount of reduction being proportional to the concentration of alcohol in the breath sample.

Fuel Cell

In the fuel cell an electro-chemical reaction between alcohol and oxygen produces an electric current proportional to the concentration of alcohol in air.

The process of analysis of a breath sample for alcohol by the fuel cell is as follows

1. The breath sample is introduced to the fuel cell

2. The alcohol in the sample is chemically oxidized at the anode

3. At the same time, oxygen (from the atmosphere) is chemically reduced at the cathode.

4. A current flow, proportional to the concentration of alcohol, is produced between the two electrodes.

DRAGER ALCOTEST 7110

The Drager Alcotest 7110 uses two means of measuring the breath alcohol concentration. One measurement is performed in an infrared cell and the other in a fuel cell. Other substances will also produce a voltage at the terminals of the fuel cell and therefore the purpose of the fuel cell is to detect the presence of any substance other than alcohol. Should there be another substance present then the reading between the fuel cell and the infrared cell will differ. If the difference exceeds 5% then the measurement process is stopped and no reading is displayed or printed. An indication of the presence of an interferent is indicated.

Measurement Process

After the instrument self tests and zero tests, the breath sample is introduced into the instrument via a delivery tube. From the delivery tube the sample enters the infrared cell and is analysed. A small portion of the breath sample in the infrared cell is taken into the fuel cell. That portion of the breath sample is analysed by the fuel cell. The instrument does two whole processes automatically. The two results are compared and then a second self-test and zero tests take place, and then the result is displayed and printed out. The instrument self-checking process takes place continually while the instrument is in use. If any of the self-checking processes detect a fault, or one result is not confirmed by the other, the instrument will indicate that a fault has been detected and will automatically abort the analysis. The instrument also aborts the analysis if a self or zero test fails.

Operating the equipment

After being switched on, the instrument takes approximately 15 minutes to warm up during which period the testing is inhibited. After warm up the testing is started and details entered via the keyboard.

After the operator information has been entered the instrument automatically pumps ambient air through the sample hose and the internal measuring cells, the instrument performs a zero test and self test. On completion of a successful zero and self test the driver has approximately two minutes to blow into the mouth piece. The sample hose is removed from its storage recess and the driver is then required to blow into the mouthpiece. Sufficient air has been blown through the sample hose when the bar graph is complete. The breath sample is now analysed for alcohol content. The measurement cell is then automatically flushed with ambient air and another zero and self-test performed. The result of the measurement is displayed on the LCD display and then printed on the printout.

Conditions when Measurements are not taken

The following conditions will result in no reading being displayed or printed (the conditions are displayed on the LCD display)

1. Check Airway-obstruction of the breath sampling system

2. Zero Test Error-contamination of ambient air

3. Insufficient Sample-no sample provided by driver

4. Alcohol in Mouth-contaminant alcohol in breath sample

5. Range Exceeded-result of analysis exceeds range of accurate measurement

6. Interferent Detected-presence of interfering substance detected

In each case the cause of termination of the test is printed together with the time and date of occurrence, followed by TEST DISCONTINUED.

LION INTOXILYSER 5000P-SA

In the Lion Intoxilizer the absorption of infrared light by ethanol at the so-called primary analytical wavelength is used to determine its concentration. To differentiate between ethanol and other organic contaminants, the absorption by the breath specimen of infrared light at three additional but characteristic secondary wavelengths is also measured. The

ratio of these four absorption measurements to each other is then compared with those taken during the initial factory calibration process of the instrument, the values of which are stored in memory. If the relative absorption values obtained on the breath specimen differ by more than a specified amount from the stored values then the presence of a substance other than ethanol i.e. an interfering substance, is detected, in which case a message “interfering substance” is indicated.

Any changes in the light beam used in the infrared cell are detected by a fifth filter, which acts as a reference. This filter transmits light at a wavelength where ethanol and any other contaminants do not absorb the infrared light. The infrared light is detected and comprehension for any changes in light intensity is made.

These five filters are housed on a wheel that rotates at 2 400 revolutions per minute. This means that infrared absorption is measured at each of the five wavelengths forty times per second.

Measurement Process

After the instrument self and zero tests, the breath sample is introduced into the instrument via a delivery tube. From the delivery tube the sample enters the infrared cell and is analysed. The instrument does the whole process automatically. A second self and zero tests take place, and then the result is displayed and printed out.

The instrument self-checking process takes place continually while the instrument is in use. If any of the self-checking processes detect a fault the instrument will indicate that a fault has been detected and will automatically abort the analysis. The instrument also aborts the analysis if a self or zero tests fails.

Operating the equipment

After switch on, the instrument takes approximately 15 minutes to warm up during which period the testing is inhibited. After warm up the testing is started and details entered via the keyboard.

After the operator information has been entered the instrument automatically pumps ambient air through the breath tube and the internal measuring cells, the instrument performs an Air Blank test. On completion of a successful Air Blank test the driver has approximately three minutes to blow into the mouthpiece. The sample hose is removed from its storage recess and the driver is then required to blow into the mouthpiece. This 3-minute period allows up to 5 attempts to blow. Indication that sufficient air has been blown through the sample hose occurs when the tone stops. The breath sample is now analysed for alcohol content. The measurement cell is then automatically flushed with ambient air and another Air Blank test performed. The result of the measurement is displayed on the LCD display and printed on the printout.

Conditions when Measurement are not taken

The following conditions will result in no reading being displayed or printed (the conditions are displayed on the LCD play)

1. Specimen Incomplete- Subject has not provided required specimen (1,2 litres of

breath) within 3 minutes.

2. Mouth Alcohol-Residual mouth alcohol detected

3. Interfering Substance- Substance other than ethanol detected

4. Ambient Air Fail-Air Blank reading of 0 mg/l not obtained.

5. Out of range-Subjects breath alcohol level exceeded 2.2 mg/l

In each case the cause of termination of the test is printed together with the time and date of occurrence.

6. Computer and software requirements-Computer and Peripheral Hardware, Software

Requirements, Software Operational Requirements.

As the specification covers a large number of tests, some of which are destructive, type testing is performed on a sample of each make and model of EBT. Note that not each and every EBT of a particular make and model is subject to testing to SABS 1793, as this is impractical.

In order to ensure that EBT’s remain within the limits of accuracy as specified by SABS 1793 each and every unit should be subject to calibration testing periodically. This usually takes place every six months. It does not mean however that the equipment is no longer accurate after 6 months but is rather to give confidence firstly to the operator and secondly to the courts that the equipment is accurate.

Calibration testing only tests the accuracy of measurement at a number of concentrations of ethanol in air, usually at the legislated limit and at one level below and one level above the limit. It does not test for compliance with all the requirements of the SABS specification. Calibration can be done by using a calibrated gas concentration (dry gas method) or a wet bath simulator. At present the CSIR calibrate the EBT’s using the dry gas method.

RELATIONSHIP BETWEEN BLOOD ALCOHOL AND BREATH ALCOHOL

Alcohol is absorbed through the alimentary canal into the blood stream in which it is distributed throughout the body affecting the nervous system, especially the brain. The blood alcohol level is a measure of the degree to which a person is likely to be affected. In the past blood samples have been taken and subjected to a complicated analysis to determine the concentration of alcohol in the blood.

Taking a blood sample is invasive and its analysis is intricate and time-consuming. Fortunately alcohol is a drug, which is volatile enough to appear in the expired breath. Thus some of the alcohol, which has been consumed and absorbed into the blood, evaporates into the air in the lungs. The concentration of alcohol in a person’s breathe

Is dependent on the concentration of alcohol in the blood. The higher the blood alcohol levels the higher the breath alcohol level, and vice versa. This relationship follows well-established physical and physical and physiological principles. Thus breath alcohol analysis is also a measure of the degree to which a subject is affected by the consumption of alcohol.

The method by which alcohol gets into the blood stream and thence into the breath is initially through the stomach and intestines. The liquids (alcoholic drink) passes quickly from the mouth into the stomach and then more slowly into the small intestine. Very little

alcohol is absorbed through the mucus lining of the mouth and the stomach: the vast majority is absorbed through the walls of the small intestine. The duodenal walls are permeable to small compounds such as nutrients from digested food. Food is broken down by enzyme action in the intestine and the nutrients are small and soluble enough to pass through the walls of the gut, which are richly supplied by the blood vessels. The blood absorbs and carries away the nutrients from the digested food. This process of digestion requires time whereas alcohol being a small soluble molecule requires no such breakdown.

It diffuses directly into the walls of the digestive tract entering the blood in the network of capillaries supplying these organs. (This explains the rapid effect of alcohol consumption) The capillary vessels feed ultimately into the portal vein, which carries the blood with the nutrients and the alcohol to the liver where some of the alcohol (and certain desirable components from the digestive tract) is eliminated. The rest is transported to all parts of the body, including the brain.

The blood from the intestine goes via the liver and joins the used blood from other organs in the vena cava and flows to the right-hand side of the heart. From the right ventricle the blood is pumped to the lungs via the pulmonary artery. In the lungs the blood vessels divide and subdivide becoming capillaries that line the tiny airspaces, the alveoli, containing deep lung air. The alveoli are fine capillaries created by the branching and rebranching of the bronchial tubes. The tissues of the lung are so thin the blood and the air are virtually in contact facilitating the exchange of oxygen and carbon dioxide. If the blood contains alcohol some of the alcohol is lost into the alveolar air, the amount of alcohol going into the air of the lungs is proportional to the amount of alcohol in the blood. This is how the alcohol gets into the breath.

From the lungs the blood returns to the left ventricle of the heart via the pulmonary vein, from where the fresh blood (and alcohol if present) is pumped to the various organs of the body. The brain is richly supplied. Alcohol that is absorbed into the blood is quickly distributed throughout the body.

From the liver the blood flows to the heart whence it is pumped through the lungs. In the lungs the blood is aerated gaining oxygen and giving up carbon dioxide. If the blood contains alcohol some of the alcohol is lost into the alveolar air: the amount going into the air of the lungs is proportional to the amount of alcohol in the blood. The relationship between breath alcohol level and blood alcohol level follows Henry’s Law which states that if one has a given concentration of vapour (alcohol) in the air then, at equilibrium, one would have a definite concentration of that material in the liquid (blood).

From the lungs the oxygenated blood (containing alcohol if present) returns to the heart for

Distribution throughout the body, the brain being richly supplied. For an average healthy man each heartbeat displaces about 70ml of blood. Since at rest the average heart rate is about 70 beats per minute the heart will pump about 5 litres per minute. As an average man has about 5 litres of blood (woman about 4.5 litres) in the blood vascular system, the

blood circulates quickly and freely. Alcohol that is absorbed into the blood is therefore quickly distributed throughout the body.

The alcohol in the blood is eliminated mainly through the action of the liver (95%) where it is broken down to carbon dioxide and water. The remaining alcohol (5%) is eliminated unchanged in the urine-very small amounts are eliminated in the breath and perspiration.

Evidential Breath Testing

The test for breath alcohol requires that breath in equilibrium with the blood be tested, that is alveolar air. For this reason sufficient breath must be exhaled during the test to ensure that alveolar air is measured; corridor air contains lesser amounts of alcohol in the exhaled breath with increasing levels of alcohol until a plateau is reached which will be the alcohol in the alveolar air. This will require about one litre of breath to be exhaled through the instrument detect an aberration in the test will be aborted.

Mention is sometimes made that the presence of mouth alcohol can affect the results of breath alcohol testing since the procedure requires a sample of lung air to be blown into the instrument through a mouthpiece. Mouth alcohol would result in the instrument initially detecting a high alcohol level followed by a lower level from the upper lung air and then a different level from the deep lung air. This would be a deviation from the expected normal test, and the test would be terminated and no result recorded. Before a subject is to be tested the procedure should include a waiting period of at least 20 minutes before the test commences. After this time any mouth alcohol would have then been swallowed or absorbed.

Any mixture which contains alcohol and which is taken by mouth will contribute to the alcohol in the body, so the alcohol in a cough mixture will be absorbed in the same way as alcohol in alcoholic beverages.

The specification for evidential breath testing equipment requires that foreign gases (such as methanol, isopropanol, acetone, ethyl acetate and toluene) that could be in a breath sample together with alcohol should cause no cross-sensitivity in the evidential breath test, or cause no excessive variation, failing which the test would be automatically discontinued. Sometimes persons with severe diabetes could have acetone in their breath at a higher level than the equipment is designed to tolerate, in which case the instrument would automatically terminate the test.

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Thirty DUI Cases That Will Help You Win

January 8, 2007 by alabamadui

THIRTY DUI CASES FROM OTHER JURISDICTIONS THAT WILL HELP YOU WIN ALABAMA CASES

ISSUE: REASONABLE, ARTICULABLE SUSPICION FOR THE DUI STOP

1. Rowe v. State, 363 Md. 424, 769 A. 2d 879 (2001).
2. Frasier v. Driver and Motor Vehicle Services Branch (DMV), 271 Ore. App. 215 (2001).
3. United States v. Gregory, 79 F. 3d 973 (10th Cir. 1996).
4. Crooks v. State, 710 So. 2d 1041 (Fla. App. 1998).
5. State v. Caron, 534 A. 2d 978 (Maine 1987).
6. United States v. Chanthasouxat, 342 F. 3d 1271 (11th Cir. 2003).
7. State v. Puckett, No. E2002-01959-CCA-R3-CD (Tenn. Crim. App. decided July 9, 2003).
We all know that weaving within a lane, although not an offense, can justify a stop. Smith v. State, 236 Ga. App. 548 (1999). However, as in Smith the Court of Appeals has consistently characterized the kind of driving that warrants a brief investigative detention as “erratic.” E.g., Davis v. State, 236 Ga. App. 32 (1999); Arsenault v. State, 257 Ga. App. 456 (2002). Somewhat more elusive is a definition of weaving in the Georgia case law, but “…a continuous failure on the part of the driver to maintain a direct line of travel within his lane”, State v. Bailey, 51 Ore. App. 173, 624 P. 2d 663 (1981), should suffice.
The failure to maintain lane statute, O.C.G.A. 40-6-48, has counterparts in every state, and every statute employs identical or nearly identical language. One of the most recent decisions that reviewed a plethora of case law is Rowe v. State, 363 Md. 424, 769 A. 2d 879 (2001). In that case the arresting officer noticed the Appellant’s van cross the “white edge line” by about eight inches, return to the slow lane of I-95, and later touch the white line again. In reversing the Appellant’s conviction for a drug offense, the Court held that more than the integrity of lane markings, the purpose of the statute is to promote safety on laned roadways. Id. In other words, the statute is not violated unless a vehicle fails to stay within its lane and such movement is not safe or not made safely.
As the Rowe court noted, the cases in which courts have upheld traffic stops based on violations of this statute involve conduct much more egregious than that in the instant case. Specifically, they distinguished Sledge v. State, 239 Ga. App. 301 (1999) (trying to change lanes without signaling, straddling middle and slow lanes, straddling middle and left lanes); Maddox v. State, 227 Ga. App. 602 (1997) (weaving across lanes
1 of traffic onto the shoulder); State v. Holcomb, 219 Ga. App. 231 (1995) (weaving from shoulder of roadway to left lane). Other courts have interpreted language identical to that in the Georgia statute as requiring more for a violation than a momentary crossing or touching of an edge or lane line. Frasier v. Driver and Motor Vehicle Services Branch (DMV), 172 Ore. App. 215 (2001).
Maryland and Oregon are not alone. In interpreting Utah’s counterpart to O.C.G.A. 40-6-48, the Tenth Circuit Court of Appeals held that an isolated incident of a vehicle crossing two feet into the emergency lane on an interstate highway was not a violation. United States v. Gregory, 79 F. 3d 973 (10th Cir. 1996). Similarly, it has been held that, “Where a vehicle is driven on a roadway with no other traffic present, there was no speeding, erratic driving or other conduct, except for the edge line incident, to indicate that appellee was impaired, the balance is in favor of the right of privacy and against the need for a stop.” State v. Gullett, 78 Ohio App. 3d 138, 604 N.E. 2d 176 (1992) (crossing the edge line twice). Time and again, appellate courts have held that touching or going over a fog line or edge line does not justify a stop unless the driver is operating the vehicle erratically. E.g., State v. Lafferty, 291 Mont. 157, 967 P. 2d 363 (1998).
In many cases the arresting officer will concede that a defendant did not drive his car off the roadway, only drove on the fog line, and did not come close to striking another vehicle, an individual, or anything else. These facts are strikingly similar to Crooks v. State, 710 So. 2d 1041 (Fla. App. 1998), wherein the court held that even if the driver was briefly outside the margin of error, there was no objective evidence suggesting that he failed to ascertain that his movements could be made safely. Id. At 1043. The Crooks court also observed that a violation does not occur in isolation, but requires evidence that the driver’s conduct created a reasonable safety concern. Id. Once again, although weaving within a lane of traffic can justify a traffic stop, there must be something more than merely touching or even going over a fog line; there must be evidence of erratic or unsafe operation of the motor vehicle. State v. Cerny, 28 S.W. 3d 796 (Tex. App. 2000); State v. Tarvin, 972 S.W. 2d 910 (Tex. App. 1998).
Perhaps no court has gone further than holding, “A vehicle’s brief, one time straddling of the center line of an undivided highway is a common occurrence and, in the absence of oncoming or passing traffic, without erratic operation or other unusual circumstances, does not justify an intrusive stop by a police officer.” State v. Caron, 534 A. 2d 978 (Maine 1987) (straddled the center line for 25 to 50 yards). Perhaps you can suggest to your judge that you are not asking him/her to “push the envelope like your judicial brethren in Maine” but to afford the statute a common sense interpretation and limit police intrusion to those cases involving erratic driving, which means more than merely touching a fog line under circumstances that offer no hint of danger to the safety of others or their property.
2.
What about the officer’s good faith belief that a statute has been violated? Although an officer’s reasonable mistake of fact may provide the objective grounds for reasonable suspicion or probable cause required to justify a traffic stop, an officer’s mistake of law may not. United States v. Chanthasouxat, 342 F. 3d 1271 (11th Cir. 2003). The officer’s mistake of law cannot provide the objective grounds for reasonable suspicion or probable cause required to justify a traffic stop. United States v. Lopez-Soto, 205 F. 3d 1101 (9th Cir. 2000); United States v. Lopez-Valdez, 178 F. 3d 282 (5th Cir. 1999).
These Federal decisions are not inconsistent with the pronouncements of the Georgia Court of Appeals. State v. Armstrong, 223 Ga. App. 350 (1996), shed light on the mistaken interpretation of the “Laying Drags” statute. In that case the driver was spinning his tires and creating smoke in a crowded parking lot during the Christmas shopping season, thereby causing the officer to be concerned for the safety of pedestrians. Id. at 350. The key element of danger to the public overcame the Defendant’s argument that the stop was unlawful since no statute had been violated. In the typical “failure to maintain lane” case there will be no similar legitimate concern for the safety of others.
In the Interest of B.C.G., 235 Ga. App. 1 (1998) makes it clear that when “…a statute upon which an officer bases his stop is later determined to have not been violated, the stop still must be justified by specific, articulable facts sufficient to give rise to a reasonable suspicion of criminal conduct.” Id. at 5. Missing in most cases of touching the fog line, according to this analysis, is the element of danger to the public or anything that would indicate your client was about to violate the law in any manner.
Sooner or later our appellate courts will grapple with the issue of just how bad a person’s driving must be in order to justify a traffic stop. To date the reported cases involve “erratic” driving, but in my practice I am constantly confronted with cases where the client’s driving is as good as the cop’s on the way to the station the night of the arrest, the judge on the way to court in the morning, or your mother on her way to church on Sunday. The only difference is that my clients are followed (many times for mile after mile) from a bar and, therefore, touching a fog line is an excuse for stopping them. Use these non-Georgia cases, and good judges will from time to time find the police lacked the requisite articulable suspicion to detain your client.
Before we leave this subject, I want to bring to your attention one of my favorite cases from the past year, State v. Puckett, No. E2002-01959-CCA-R3-CD (Tenn. Crim. App. decided July 9, 2003). In this case the appellate court reviewed a videotape and disagreed with the arresting officer’s characterization of the appellant’s driving. The court observed that the defendant’s vehicle touched the right white line and eventually either crossed or touched the left white line. Not only was her less than perfect driving insufficient to justify a stop, but the court explicitly rejected the State’s argument that Fourth Amendment requirements should be relaxed in DUI cases. As the majority wrote, “This court simply cannot apply a different standard in reviewing the requirements for a 3. traffic stop for a DUI investigation than we would apply in reviewing any other traffic stop. The constitutional standards are not lessened, nor does the governmental officer have broader authority, because the stop is for a DUI investigation.”
ISSUE: PROBABLE CAUSE FOR THE DUI ARREST
8. State v. Taylor, 3 Ohio App. 3d 197 (1981).
9. Saucier v. State, 869 P. 2d 483 (Ak. App. 1994).
10. People v. Royball, 655 P. 2d 410 (Colo. 1982).
11. State v. Swanson, 164 Wis. 2d 437 (1991).
With the exception of State v. Batty, 259 Ga. App. 431 (2003), we do not have much in the way of good case law in Georgia. Bad facts make bad law, so perhaps we should not be surprised the Court of Appeals has held that driving over 100 miles per hour coupled with bloodshot and glassy eyes, the odor of an alcoholic beverage, and a positive result on the Alco-Sensor constituted probable cause for an arrest. See State v. Sledge, 264 Ga. App. 612 (2003). But, it gets worse. “Even in the absence of the field sobriety tests, the officer’s observation that a suspect had bloodshot, watery eyes and exuded an odor of alcohol was sufficient to show probable cause to arrest him for driving under the influence.” Cann-Hanson v. State, 223 Ga. App. 690 (1996).Observation: So why do we even need field sobriety tests?
Is there any way around this obstacle erected by the Court of Appeals? First, note that in both of the decisions cited in the preceding paragraph the defendants had “bloodshot” and “glassy” eyes. If that testimony was true, the defendants may well have been less safe drivers, but the bloodshot eyes allegedly observed by many police officers are not caused by ethanol ingestion but allergies, fatigue, smoky bars, or the pollen season. There is a difference between eyes that appear to be a bit bloodshot and the glassy eyes of a drunk. So, how do you minimize the importance of bloodshot eyes? Let’s see if NHTSA’s own studies can offer any assistance.
Appendix E of the NHTSA study (Sept. 1997, DOT HS 808 654) “The Detection of DWI at BACs Below 0.10″ concludes with the following observation: “Finally, some cues were eliminated because they might be indicators more of social class than of alcohol impairment. For example, officers informed us that a flushed or red face might be an indication of a high BAC in some people. However, the cue also is characteristic of agricultural, oil field, and other outside work. Similarly, bloodshot eyes, while associated with alcohol consumption, also is a trait of many shift workers and 4. people who must work more than one job, as well as those afflicted by allergies. A disheveled appearance similarly is open to subjective interpretation. We attempted to limit the recommendation to clear and objective post-stop behaviors.” Some officers who pride themselves on their expertise will admit that they are familiar with this study. If your client’s “bad driving” was de minimus and he or she declines field sobriety testing (which is becoming more common in my practice) as well as the Alco-Sensor (also becoming more common), what is the officer left with in many cases but the odor of alcohol? While there may be a paucity of Georgia case law on the subject, our sister states have an abundance. Before turning to that out-of-state case law, let us review the standard for determining probable cause for a DUI arrest in Georgia. The probable cause necessary for an arrest for driving under the influence was set forth in the case of Griggs v. State, 167 Ga. App. 582 (1983) which states as follows:
“As to the question of whether the arrest of defendant, for the offense of driving under the influence, was made with probable cause, we turn to the standards set forth in Beck v. Ohio, 379 U.S. 89,91 (85 SC 223, 13 LE2d 142). See also Vaughn v. State, 247 Ga. 136, 137 (274 SE2d 479). Whether the arrest was constitutionally valid depends in turn upon whether, at the moment the arrest was made, the officers had probable cause to make it —whether at that moment the facts and circumstances within their knowledge and of which they had reasonably trustworthy information were sufficient to warrant a prudent man in believing that the petitioner had committed or was committing an offense. Beck v. Ohio, 379 U.S. 89, 91, supra. The question is whether the investigating deputy at the time of defendant’s arrest had knowledge or reasonably trustworthy information that: (1) defendant was in actual physical control of a moving vehicle; (2) while under the influence of any drug; (3) to a degree which renders defendant incapable of driving safely.” (Emphasis added). The standard for probable cause remains whether the officer had knowledge or reasonably trustworthy information that a suspect was actually in physical control of a moving vehicle while under the influence of alcohol to a degree which renders him incapable of driving safely. Malone v. State, 261 Ga. App. 420 (2003). Therefore, it can surely be argued that the odor of alcohol standing alone does not provide probable cause to believe that an individual is incapable of driving safely.
Drinking and driving is not illegal in Georgia. This is specifically recognized in the pattern jury instruction which takes into account a defendant’s manner of driving, and which states, “merely showing that the defendant has been drinking, without proof of the defendant’s driving or manner of driving is not sufficient.” Suggested Pattern Jury Instructions, Volume II, Court of Superior Court Judges, Part 4, (S)(2)(f). Since Georgia does not prohibit driving an automobile after consuming 5. intoxicants, the odor of alcohol cannot reasonably and objectively provide probable cause to believe that the driver is under the influence of alcohol. This is especially true in the case where the officer does not testify to any manifestations (other than odor) commonly associated with intoxication. To conclude otherwise is to hold that conduct which is totally lawful is, without more, evidence of an offense sufficient to warrant arrest. Were this true, then “zero tolerance” would be the standard necessary to arrest rather than the standard of “under the influence to the extent that the defendant was a less safe driver.” There is no correlation whatsoever between the odor of alcohol on a person’s breath and their blood alcohol level.
The Georgia courts have never directly answered the question of whether the odor of alcohol provides sufficient probable cause for an arrest for DUI. In Clay v. State 193 Ga. App. 379 (1989), however, the Georgia Court of Appeals (in reversing the defendant’s conviction) stated in dicta that: “… the mere fact that he (the defendant) had an odor of alcohol on his breath clearly was not sufficient, in and of itself, to give rise to an inference that he was intoxicated. Indeed the state’s attorney conceded as much at trial, stating, “Certainly the smell of alcohol by itself is not an indication, but it can be an indication that somebody had been drinking…” Under the circumstances, we must conclude that the officer’s opinion that the appellant was under the influence of alcohol to the extent that it was less safe for him to drive was without evidentiary foundation.”
While Georgia has not directly decided this issue, it has been addressed by a number of other appellate courts. Beginning with State v. Taylor, 3 Ohio App. 3d. 197,198 (1981), Ohio has a long line of cases specifically stating that the odor of alcohol (even when combined with other factors) does not provide probable cause to make an arrest. In one of the more recent cases, State v. Segi, No.18267 (Ohio App. District 2), dated August 18, 2000, the arresting officer testified that the defendant Segi was arrested because he crossed the white line edge marker three times, he admitted to consuming alcohol, and had a “strong odor” of alcohol about him. Reversing the trial court’s denial of Segi’s motion to suppress, the Ohio Court of Appeals stated,”Odor of an alcoholic beverage is insufficient, by itself, to trigger a reasonable suspicion of DUI, and nominal traffic violations, being common to virtually every driver, add nothing of significance… The law prohibits drunken driving, not driving after a drink… Smelling too drunk to drive, without other reliable indicia of intoxication is not enough to constitute probable cause to arrest.”
The Court of Appeals of Alaska has summarized its position succinctly:”The mere odor of alcohol about a driver’s person…. maybe indicia of alcohol ingestion, but is no more a probable indication of intoxication than eating a meal is of gluttony.” Saucier v. State, 869 P. 2d 483 (Ak. App. 1994). 6.
Wyoming likewise has differentiated between drinking and driving and drunken driving. In Keehn v. Town of Torrington, 834 P. 2nd 112 (Wyo. 1992), the Wyoming Supreme Court stated:”A third legal reality worth noting is that it is lawful in Wyoming as in other states, to drink and drive safely. Wyo. Stat. §31-5-233 (June, 1989). A peace officer may not arrest an individual for DWUI merely because it is late at night and, during an unrelated traffic stop, the officer detects the odor of alcohol. Rather the peace officer must have probable cause to believe the individual has actual physical control of a motorized vehicle while legally intoxicated.”
Colorado has also applied this analysis even to cases which have involved motor vehicle collisions. In affirming the trial court’s suppression of the blood test based on lack of probable cause for arrest, the Colorado Supreme Court in People v. Royball, 655 P. 2d 410 (Colo. 1982), recites that:”All we learned from the record is that an accident took place, the defendant was driving one of the cars involved, and he an odor of alcoholic beverage about him. Although the officer’s testimony and his decision to administer a blood alcohol test are suggestive of an opinion that the defendant was under the influence of alcohol, the single objective fact to which he testified in support of any such conclusion is the odor of alcoholic beverage. An odor of alcoholic beverage is not inconsistent with the ability to operate a motor vehicle in compliance with the Colorado law.”(Note: The Court also specifically states that, “the prosecution has cited no case in which an odor of alcoholic beverage, without more, has been held to constitute probable cause to believe a person is under the influence of intoxicating liquor.” There also exists no such case in Georgia).
Wisconsin recently affirmed a long line of cases beginning with State v. Swanson, 164 Wis. 2d 437 (1991), that held that the odor of alcohol, even when combined with other indicia of intoxication, “may add up to a reasonable suspicion, but not probable cause.” State v. Hanson, 233 Wis 2d 89 (Wis. App. 2000). Both Louisiana and Washington, in reversing their respective trial courts, have held that even in cases involving traffic fatalities, “the mere fact that a person consumed alcohol prior to a vehicular accident does not prove that the person was under the influence or that alcohol consumption caused the accident.” State v. Garrett, 525 So. 2d 1235 (La. App. 1st Cir. 1988) and State v. Gillenwater 96 Wn. App. 667, (1999). As you can see, there is a plethora of case law from around the country holding that the odor of alcohol does not provide probable cause for a DUI arrest.
7. ISSUE: PROBABLE CAUSE FOR A DUI DRUNK DRIVING BLOOD TEST ON AN UNCONSCIOUS PERSON
12. State v. Kliphouse, 771 So. 2d 16 (Fla. App. 2000). 13. Schmerber v. California, 384 U.S. 757 (1966). On October 6, 2003, the Georgia Supreme Court held that O.C.G.A. 40-5-55 was unconstitutional to the extent that it required chemical testing of the driver of a vehicle involved in a traffic accident resulting in serious injuries or death regardless of any determination of probable cause. Cooper v. State, 277 Ga. 282 (2003). But what is the standard for determining if probable cause exists to obtain a blood test of a driver rendered unconscious in an accident.
State v. Kliphouse, 771 So. 2d 16 (Fla. App. 2000) provides some guidance. In that case the appellee was driving a motorcycle when he was struck by a car and rendered unconscious. A police officer arrived at the scene and smelled alcohol on the appellee’s breath. While he was still unconscious the officer requested medical personnel to draw a blood sample at the hospital. The issue, as framed by the court, was: Does the mere odor of alcohol on the breath of a driver, who was involved in an accident not in any way attributable to said driver, without other indicia of impairment, give an officer reasonable cause to believe that the driver was under the influence of alcohol…?” The court noted that, “As the trial court observed, the presence of an odor of alcohol alone is generally not considered an accurate and reliable measure of impairment and, thus, is rarely deemed sufficient for a finding of probable cause.” Id. At 23. In other words, if a driver was not responsible for an accident and is rendered unconscious by injuries sustained in the accident, the odor of alcohol alone not will justify a search of his blood by the state.
This situation is distinguishable from a case where a motorist drives his car off the roadway, strikes a tree, smells of liquor, and the condition of his eyes is “bloodshot, watery, sort of a glassy appearance.” In that case, probable cause for the search exists. Schmerber v. California, 384 U.S. 757 (1966). The same court that decided Kliphouse has held that the smell of alcohol on a defendant’s breath, along with evidence that the driver had caused an accident resulting in serious bodily injury, gave the officer sufficient probable cause to request a blood test. State v. Cesareti, 632 So. 2d 1105 (1994).
8. ISSUE: ADMISSIBILITY OF FIELD SOBRIETY TESTS IN DRUNK DRIVING LAWS
14. State v. Homan, 89 Ohio St. 3d 421 (2000).
15. State v. Schmitt, 101 Ohio St. 3d 79 (2004). 16. State v. Lasworth, 131 N.M. 739, 42 P. 3d 844 (N.M. App. 2001).
17. United States v. Horn, 185 F. Supp. 2d 530 (D. Md. 2002). 18. State v. Chastain, 960 P. 2d 756 (Kan. 1998).
Although an examination of Georgia case law pertaining to field sobriety testing is beyond the scope of this paper, and was covered during the morning session, even a cursory review of the decisions from our Court of Appeals reveals that they have taken a very relaxed approach to the admissibility of field sobriety tests. Their approach has won less than universal approval. In State v. Homan, 89 Ohio St. 3d 421 (2000), the Ohio Supreme Court ruled that in order for the results of field sobriety tests to serve as evidence of probable cause to arrest, the police must have administered the tests in strict compliance with standardized testing procedures. Obviously, if the test “results” were inadmissible to determine probable cause to arrest, they were inadmissible at trial.
Following the Homan decision the Ohio legislature “fixed the problem” by enacting a statute providing that an arresting officer need not administer the FST’s in strict compliance with his training in order for the “results” to be admissible at trial. Instead, an officer may now testify concerning the results if the FST’s are administered in substantial compliance with the standards. The Supreme Court of Ohio has since ruled that prior to the effective date of the statute testimony based on the officer’s firsthand observation of the defendant’s conduct and performance as a lay witness is admissible, but the Court still prohibited testimony regarding the test results, which may be tainted, if the tests are not conducted “by the book.” State v. Schmitt, 101 Ohio St. 3d 79 (2004). The court also explicitly extended the Homan rule to the admissibility of test results at trial. We all know that Drs. Marcelline Burns and Herbert Moskowitz, doing business as the Southern California Research Institute, conducted research on field sobriety tests back in the 1970’s under a NHTSA contract. Prior to her appearance in State v. Lasworth, 131 N.M. 739, 42 P. 3d 844 (N.M. App. 2001), Dr. Burns had been recognized as an expert on horizontal gaze nystagmus in at least twenty-six states. A plucky trial judge ruled that, although Dr. Burns could testify as to the reliability of HGN, she was not qualified to establish its validity. Under New Mexico law, before scientific evidence may be admitted, the proponent must convince the trial court that the technique 9. has scientific validity. In other words, there must be proof of the technique’s ability to show what it purports to show. State v.Alberico, 116 N.M. 156, 167 (1993).
The appellate court agreed with the trial court that without a more detailed understanding of the causes of HGN, they could not be sure the results obtained by Dr. Burns, et. al., were not a “coincidence.” The court then reviewed the 1995 Colorado FST validation study and made some interesting observations. The mean BAC of the 234 motorists who were detained was .152. Of the 234 motorists, 184 had BAC’s in excess of the statutory limit. If the police had simply arrested every one of the 234 drivers, seventy-nine percent of their arrest decisions would have been correct. In the actual study the arrest decision was correct eighty-six percent of the time, so FST’s had only a marginal impact on correct decision making. Furthermore, even Dr. Burns has conceded that lack of smooth pursuit and distinct nystagmus at maximum deviation occur at low BAC’s with some people but not others or on some occasions but not others. She has also admitted that there is evidence that smooth pursuit may break down at BAC’s as low as .04 and that controlled experiments at low BAC’s are needed. Because these statements suggest that the HGN may be prone to false positives under New Mexico law, the appeals court opined that it was reasonable for the trial court to want to know more about the effects of low alcohol levels on the physiological mechanisms that produce HGN. It gets better. The court noted that HGN was originally “validated” as a means of distinguishing BAC’s below .10 and those at or above .10. In the 1995 Colorado study the FST battery was used to distinguish BAC’s above or below .05, and in the same study Dr. Burns suggested the FST’s are also effective when the criterion for arrest is .08. As the appeals court said, “The district court could reasonably have wanted to hear a more detailed scientific explanation of how the physiological cues that make up the HGN FST vary with a subject’s BAC in such a remarkable manner that the HGN FST can provide statistically valid and reliable evidence at varying criterion BAC’s.
The magnum opus on FST’s must be United States v. Horn, 185 F. Supp. 2d 530 (D. Md. 2002). The defendant called Spurgeon Cole, Ph.D., Professor of Psychology at Clemson University, Yale Caplan, Ph.D., former chief toxicologist for the Office of the Medical Examiner in Maryland, Joel Wiesen, Ph.D., an industrial psychologist, and Harold Brull, a licensed psychologist, who testified either in person or by affidavit, that the tests were unreliable to prove a person was impaired by alcohol. Dr. Cole was particularly critical of the methods used by NHTSA to test and validate the FST’s. He noted the unacceptably high error rates of 47% in the 1977 study and 32% in the 1981 Final Report, which were both eclipsed by the inter-rater reliability rate of only 57%. Dr. Cole’s own study showed officers classified 46% of sober individuals as too impaired to drive. Of course, the studies upon which NHTSA had relied were not subjected to peer review nor published in the sense contemplated by Daubert.
10.
The magistrate ruled that:
1.Results of properly conducted FST’s are admissible to show probable cause to arrest.
2. FST’s cannot be used to establish a blood alcohol content.
3. HGN has been shown to be caused by alcohol consumption among other reasons.
4. If the officer is properly trained and qualified to perform FST’s he may testify about his observations only, without referring to terms like “failed the test” or “exhibited” a number of “standardized clues.”
5. If the officer testifies he performed and observed HGN, the defendant may bring out the numerous other causes of HGN through cross-examination or judicial notice.
6. The officer’s lay opinion cannot include his technical or specialized knowledge concerning HGN.
Although many courts across the country have casually admitted HGN evidence by reference to NHTSA materials or other court decisions, a handful have actually excluded HGN evidence. State v. Chastain, 960 P. 2d 756 (Kan. 1998), found that HGN does not satisfy the Frye standard and is, therefore, inadmissible before the trier of fact. Mississippi, while allowing HGN evidence for probable cause determinations, has also held that HGN does not satisfy Frye. Young v. City of Brookhaven, 693 So. 2d 1355 (Miss. 1997).
11. ISSUE: ADMISSIBILITY OF STATE ADMINISTERED BREATH TESTS IN DUI CASES
19. Patton v. City of Decatur, 337 So. 2d 321(Ala., l976).
20. Fuenning v. Superior Court, 139 Ariz. 590, 680 P. 2d 121 (1984).
21. Mayo v. City of Madison, 652 So. 2d 201(Ala., l994).
The vast majority of states have statutory requirements very similar to O.C.G.A. 40-6-392 (a), which is based on the Uniform Motor Vehicle Code. It has been uniformly held that blood and breath test results are not admissible under these shortcut statutes if it cannot be shown that the tests were conducted in accordance with the “methods approved” by the responsible state agency. E.g., State v. Broyles, 94 Ore. Appp. 334, 765 P. 2d 239 (1988); Westerman v. State, 1974 Ok. Cr. 151, 525 P. 2d 1359 (1974). It goes without saying that a test cannot be performed according to approved methods if there are no approved methods.
Last year the Court of Appeals deflected a frontal assault daring the State to reveal both the existence and content of their illusory approved methods. Scara v. State, 259 Ga. App. 510 (2003). This year they have gone even farther and held that the instructions in the Intoxilyzer 5000 operator’s manual are not part of the methods approved by DFS, so a deviation therefrom goes to weight and not admissibility. State v. Palmaka, 2004 WL 595320 (Ga. App. decided March 26, 2004).
Currently, Ga. Comp. R. & Regs. R. 92-3-06 (12) provides that, “Administrative, procedural, and or/clerical steps performed in conducting a test shall not constitute a part of the approved method of analysis.” Basically, DFS is saying, “How we do it is not a part of how we do it.” While I must reluctantly concede that I do not expect our Court of Appeals to rectify the situation in my lifetime, perhaps some day the persuasive precedents from across the country will sway our Supreme Court. The Supreme Court of Alabama faced a situation not unlike the current state of affairs in Georgia when they decided Patton v. City of Decatur, 337 So. 2d 321(Ala., l976). The Alabama statute provided that, “Chemical analyses of the person’s blood, urine, breath to be considered valid under the provisions of this section shall have been performed according to methods approved by the State Board of Health…” In Patton the police officer testified that he had a license issued by the appropriate State authority to operate the breath testing device. In fact, that officer went farther than the officer in Scara and testified as to the procedure he followed, which was printed in the form of a check list on a card. The trial court had before it no certified methods promulgated by the
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Board of Health for the administration of breath tests. The Alabama Supreme Court ruled that their inability to ascertain the validity of the results demonstrated the absolute necessity for written procedural methods governing its use. Id. at 324. The Court also observed that unwritten standards were the equivalent of having no standards at all. As in Patton, no Georgia court has before it any evidence concerning the content of the “methods approved by the Division of Forensic Sciences” other than “How we do it is not a part of how we do it.”
The Division of Forensic Sciences and prosecutors all over the state apparently expect our courts to accept the proposition that “procedural steps” are not part of the approved methods, and in Palmaka the Court of Appeals implicitly did so. My research has yielded only one reported appellate decision wherein the State explicitly put forward this proposition. In rejecting this method-procedure dichotomy, the Supreme Court of Arizona noted that method and procedure are interchangeable words. Fuenning v. Superior Court, 139 Ariz. 590, 680 P. 2d 121 (1984).
The appellate courts of other states have gone even further in requiring compliance with the requirement that breath tests be conducted according to methods approved by the applicable state agency. For example, it has been held that the state’s failure to specify inspection procedures as part of their published administrative rules prohibited the prosecutor from proving that the chemical analysis was “performed according to methods approved by the Department of Forensic Sciences.” Mayo v. City of Madison, 652 So. 2d 201(Ala., l994). The Court observed that, at a minimum, DFS should adopt particularized rules to ensure that the Intoxilyzer 5000 machines are effectively inspected for accuracy and reliability. Id. At 209. Interestingly, the rule in effect in Alabama at the time merely provided that each breath testing machine would be checked periodically and lacked any specific instructions regarding how the machine would be inspected, what standards would be employed to determine that a machine was sufficiently accurate, nor what parts of the machine would be checked. In other words, the Alabama rule that was found lacking by the Mayo court is exactly what we have in Georgia today. Ga. Comp. R. & Regs. R. 92-3-.06 (8) provides, in part, that, “The Director, Division of Forensic Sciences: (a) will cause each instrument used in the administration of breath tests to be checked periodically for calibration and operation and a record of the results of all such checks to be maintained.”
The purpose of requiring published techniques and methods is to make the court’s job easier. If proper, published regulations existed regarding the operation of the machine, the maintenance of the machine, and the competence and qualifications of permit holders, the court could simply go down the list and admit the test result, confident that the testing process met scientific standards that have been promulgated in an open setting and determined to be fair.
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The existing GBI implied consent rules can be summarized as follows: “We will approve whatever machine we want to, we will calibrate it whenever we feel like it, we will calibrate it to whatever standard we feel like, and we will issue permits to whoever we want. We will not publish any of our rules, and they are subject to change without notice. Go read the Forensic Sciences Act of 1997.”
ISSUE: FAILURE TO PRESERVE EXCULPATORY EVIDENCE IN DUI CASES
22. California v. Trombetta, 467 U.S. 479 (1984).
23. Arizona v. Youngblood, 488 U.S. 51 (1988).
24. State v. Meza, 203 Ariz. 50, 50 P. 3d 407 (Ariz. App. 2002). 25. Ex parte Gingo, 605 So. 2d 1237 (Ala. 1992).
California v. Trombetta, 467 U.S. 479 (1984), involved a due process challenge to a DUI conviction where the state failed to preserve the defendant’s breath sample. The Court rejected the defendant’s argument, reasoning that samples were unlikely to be exculpatory since the procedures for running the Intoximeter rendered the results reliable. However, the Court’s conclusion was premised on the reliability of the breath testing instrument and the fact that California law gave the defendant the opportunity to inspect the machine as well as that machine’s weekly calibration results and the breath samples used in the calibrations. Trombetta did hold that the government violates due process when it fails to preserve evidence containing a known exculpatory value and comparable evidence is not obtainable by reasonable means. In other words, a due process challenge will be sustained when the exculpatory value of the evidence is apparent before it is destroyed.
In Arizona v. Youngblood, 488 U.S. 51 (1988), the Supreme Court held that unless a criminal defendant can show bad faith on the part of the police, failure to preserve potentially useful evidence does not constitute a denial of due process of law. Justice Stevens’ concurring opinion is notable for the remark that, “In my opinion there may well be cases in which the defendant is unable to prove that the State acted in bad faith but in which the loss or destruction of evidence is nevertheless so critical to the defense as to make a criminal trial fundamentally unfair.”
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For a case where an appellate court found bad faith requiring suppression of a breath test result, please read State v. Meza, 203 Ariz. 50, 50 P. 3d 407 (Ariz. App. 2002). The Arizona Court of Appeals held that the state’s failure to disclose Alcohol Data Acquisition Management System (ADAMS) records violated discovery rules, the State crime lab acted in bad faith when it concealed results of the breath analyzer’s failed calibration tests from ADAMS and the defendant, suppression of test results was the appropriate sanction, and the defendant was entitled to a restitutionary monetary sanction to alleviate the costs undertaken due to discovery violations.
In a case where bad faith was not shown, the Alabama Supreme Court excluded test results in a hazardous waste disposal prosecution. Ex parte Gingo, 605 So. 2d 1237 (Ala. 1992). Distinguishing Youngblood the court observed that in this case there was no evidence available to refute the test results because the samples had been destroyed, and the very evidence necessary to convict the defendants was the test results. In other words, the defendants were indicted solely because of the test results done on the samples. Citing Justice Stevens’ concurring opinion in Youngblood the unanimous Court excluded the State’s test results. This case might be of use in that limited number of instances where the crime lab destroys blood or urine samples in a DUI-drugs case before you are retained. This would be especially true in a case where the arresting officer does not have the relevant skills, experience, or training to render an opinion as an expert on the issue of whether your client was under the influence of a drug. See People v. Workman, 312 Ill. App. 3d 305, 726 N.E. 2d 759 (2000).
15. ISSUE: DUI COLLATERAL ESTOPPEL – DUI CRIMINAL vs. DUI CIVIL TRIALS
26. Gumma v. White, 345 Ill. App. 3d 610, 803 N.E. 2d 130 (2003).
It seems well established that the state is not collaterally estopped from presenting evidence that a defendant refused to submit to state test at defendant’s trial for DUI because an administrative law judge found that the police officer who stopped the defendant failed to properly inform the defendant of his/her implied consent rights. The ALJ’s decision has no preclusive effect in a criminal trial because the state did not have a full opportunity to litigate the issue of whether the defendant refused testing during the administrative hearing. Swain v. State, 251 Ga. App. 110 (2001). Please note that in Swain, unlike earlier cases, an evidentiary hearing was held and the ALJ reached a decision on the merits.
There are four requirements for application of the doctrine of collateral estoppel: 1. Both proceedings must involve the same parties or their privies. 2. The issue must have been actually litigated and determined in the first proceeding. 3. The determination must have been essential to the judgment in the first proceeding. 4. The party against whom the doctrine is asserted must have had a full opportunity to litigate the issue in question.
The Swain court said that even if the first three criteria had been met, the last had not. Affording great weight to the fact that only the driver, and not the State, may seek judicial review of an ALJ’s decision, the court concluded that the State did not have a full opportunity to litigate the issue of whether Ms. Swain refused testing. The court also emphasized that the purpose of the driver’s license suspension hearing was to provide a quick, informal procedure to remove dangerous drivers from Georgia’s roadways. The court also cited the Supreme Court of Illinois for the proposition that to rule otherwise would make it necessary for the State to treat the suspension hearing as an integral part of the criminal trial, so the process would seldom, if ever, be swift. People v. Moore, 138 Ill. 2d 162, 561 N.E. 2d 648 (1990).
Why would reliance on the Illinois decision be important? In Gumma v. White, 345 Ill. App. 3d 610, 803 N.E. 2d 130 (2003), the Illinois Court of Appeals distinguished the situation where the criminal proceeding has preceded the administrative hearing. Mr. Gumma’s breath was held inadmissible because the police had failed to maintain records required by Illinois Administrative Code, and the DUI charge was dismissed. Therefore, the rationale of the Moore decision, that the administrative process be swift, was inapplicable, and collateral estoppel precluded the suspension of Mr. Gumma’s license. This decision will be of limited applicability in Georgia because a non-DUI disposition of the underlying charge results in deletion of the administrative suspension, but at least in cases of alleged refusal it will be of some utility.
16. ISSUE: DUI DWI Drunk Driving ROADBLOCKS
27. State v. McCleery, 251 Neb. 940, 560 N.W. 2d 789 (1997). 28. Commonwealth v. Buchanon, 122 S.W. 3d 565 (Ky. 2004).
In State v. McCleery, 251 Neb. 940, 560 N.W. 2d 789 (1997), the issue was whether stopping one’s car one-fourth of a block from a sobriety checkpoint and then backing away from the checkpoint constitutes sufficient evidence to have a reasonable suspicion that the driver is, has been, or is about to be engaged in criminal behavior. The checkpoint was conducted in total compliance with the Department of Transportation policy, and a DOT report on “The Use of Sobriety Checkpoints for Impaired Driving Performance” provides in part, “A motorist who wishes to avoid the checkpoint by legally turning before entering the checkpoint area should be allowed to do so unless a traffic violation is observed or probable cause exists to take other action. The act of avoiding a sobriety checkpoint does not constitute grounds for a stop.” So, the Nebraska Supreme Court reversed the trial court’s order denying defendant’s motion to suppress all evidence obtained pursuant to her unlawful detention.
The case from Kentucky is interesting, and with Baker on the books should be persuasive in Georgia. The Court held that the evidence indicated that the primary purpose of a roadblock conducted by the sheriff’s department, which was conducted by the department placing a “spotter” several hundred yards before the roadblock who radioed ahead if a vehicle looked “suspicious,” was the interdiction of illegal drugs, and thus the roadblock was in violation of the Fourth Amendment. Commonwealth v. Buchanon, 122 S.W. 3d 565 (Ky. 2004). The court was not persuaded by the clever sheriff’s tactic of placing signs announcing a DUI roadblock by the side of the highway.
17. ISSUE: THE JUSTIFICATION AND NECESSITY DUI DEFENSE
29. Stodghill v. State, 2004 WL 193187 (Miss. App. decided February 3, 2004).
30. People v. Pena, 197 Cal. Rptr. 264 (Cal. Ct. App. 1983).
While I am unaware of any Georgia case law addressing the justification and necessity defense in a DUI case, I have successfully used the defense on one occasion. We do have one case holding that the defense is available in a habitual violator prosecution. The defendant was charged while driving his very pregnant wife to the doctor, and the trial court refused to charge the jury on the justification defense. The Georgia Supreme Court reversed the conviction and ruled that a jury could have found that seeking medical help was proper justification, so the instruction should have been given. Tarvestad v. State, 261 Ga. 605 (1991).
Stodghill v. State, 2004 WL 193187 (Miss. App. decided February 3, 2004), reminds me of the case I tried several years ago. Mr. Stodghill and his girlfriend were spending the night at a cabin in a remote location when she became violently ill with seizure-like activity. He was unsuccessful in summoning an ambulance on his cell phone, so he decided to drive her to the hospital. He was, of course, stopped, charged with DUI, and convicted. In reversing the conviction the Court of Appeals noted that three elements must be established by the defendant: 1) the act charged must have been done to prevent a significant evil; 2) there must have been no adequate alternative; and 3) the harm caused must not have been disproportionate to the harm avoided.
And now for my favorite case of the thirty, People v. Pena, 197 Cal. Rptr. 264 (Cal. Ct. App. 1983). A deputy sheriff observed the defendant and his girlfriend asleep in his car and decided to investigate because of the late hour. Upon approaching the car, the officer stated that he smelled alcohol. The girlfriend was semi-nude, wearing only a long fur coat over a “brief see-through teddy nightgown.” The deputy then conducted what he claimed was a search for weapons, examining the lady’s body under her fur coat with a flashlight and continuing his examination of the lady’s rear. He then ordered her into his patrol car to take her home, ostensibly for her protection.
Proving that chivalry is not dead, the defendant followed them out of fear for his girlfriend’s safety and was arrested at her house for DUI. The California Court of Appeals held that the defense was available to the defendant and that he would be entitled to an acquittal, notwithstanding the fact that he was legally intoxicated, if he could establish the defense on the facts by convincing the jury that: 1) he held a genuine belief that the lady was in danger of assault by or through the deputy, 2) his good faith belief was objectively reasonable under the totality of the circumstances, 3) he operated his vehicle only because of his fear for the girlfriend’s safety and for no other purpose, 4) he had no opportunity to engage in alternative legal means of protecting his girlfriend from the danger he believed she faced; and 5) he was not substantially at fault in the creation of the emergency situation which he claims justified his action in driving while intoxicated.
While rare, these cases can and do arise. And remember, when the use of a flashlight and the circumstances don’t quite fit, you must acquit.

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Statistical Evaluation of Standardized Field Sobriety Tests

January 8, 2007 by alabamadui

In Press: Journal of Forensic Sciences. May, 2005
Statistical Evaluation of Standardized Field Sobriety Tests
Michael P. Hlastala1, Ph.D.; Nayak L. Polissar2, Ph.D.; and Steven Oberman3, J.D.
1. Division of Pulmonary and Critical Care Medicine, Department of Medicine, Department of Physiology and Biophysics, University of Washington, Seattle, WA 98195-6522 2. The Mountain-Whisper-Light Statistical Consulting, Seattle, WA 98112 3. Daniel and Oberman, an Association of Trial Lawyers, 550 W. Main St., Suite 950; Knoxville, TN 37902 Running Head: Field Sobriety Test Accuracy
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ABSTRACT: Standardized Field Sobriety Tests (SFSTs) are used as qualitative indicators of impairment by alcohol in individuals suspected of DUI. Stuster and Burns authored a report on this testing and presented the SFSTs as being 91% accurate in predicting Blood Alcohol Concentration (BAC) as lying at or above 0.08%. Their conclusions regarding accuracy are heavily weighted by the large number of subjects with very high BAC levels. This present study re-analyzes the original data with a more complete statistical evaluation. Our evaluation indicates that the accuracy of the SFSTs depends on the BAC level and is much poorer than that indicated by Stuster and Burns. While the SFSTs may be usable for evaluating suspects for BAC, the means of evaluation must be significantly modified to represent the large degree of variability of BAC in relation to SFST test scores. The tests are likely to be mainly useful in identifying subjects with a BAC substantially greater than 0.08%. Given the moderate to high correlation of the tests with BAC, there is potential for improved application of the test after further development, including a more diverse sample of BAC levels, adjustment of the scoring system and a statistically-based method for using the SFST to predict a BAC greater than 0.08 %.
KEYWORDS: forensic science, alcohol, intoxication, horizontal gaze nystagmus, one leg stand, walk and turn.
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In August of 1998, The National Highway Traffic Safety Administration published on their web page, a final report entitled “Validation of the Standardized Field Sobriety Test Battery at BACs Below 0.10%” (1) as a follow-up to the original work of Burns and Moskowitz (2) and of that of Tharp et al (3). This report has been used as a standard for Field Sobriety Testing (FST) by law enforcement agencies around the US. In the report, authors Stuster and Burns conclude that the use of SFSTs for “estimates of the 0.08% level were accurate in 91 percent of the cases, or as high as 94 percent “if explanations for some of the false positives are accepted”. However the conclusion regarding accuracy is strongly influenced by the large number of subjects with BAC levels much greater than the 0.08% level The accuracy is substantially less for individuals with lower BAC levels, as will be shown below. Three additional papers have recently been published addressing accuracy of sobriety tests at lower alcohol levels. McKnight et al (4) evaluated BAC levels below 0.10 using Horizontal Gaze Nystagmus (HGN) and other modified tests. These authors used correlation analysis and concluded that HGN was the only valid indicator effective in identifying subjects between BAC levels of 0.04% and 0.08%. Another study by Heishman et al (5) focused on ethanol at low levels, cocaine and marijuana using correlation analysis with a variety of variables in addition to the SFSTs so it is difficult to correlate with the Stuster and Burns data. Cole and Nowaczyk (6) studied 21 sober (non-drinking) subjects using trained police officers to evaluate the SFSTs using videotapes of the individuals performing SFSTs. Forty-six percent of the officers’ decisions were that the individual had “too much to drink”.
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SFSTs are usually used as tools by officers in the field to determine if an arrest followed by a breath test is justified. However, often breath test results are not available in court for a variety of reasons. Under these circumstances, the SFST’s are frequently used as an indication of impairment and sometimes as an indicator that the subject has a BAC greater than 0.08 g/dl.
The purpose of this report is to outline the statistical strengths and weaknesses of the Stuster and Burns report (1) (SBR) and to suggest some improvements in the use of SFSTs. Our findings suggest that the SFSTs may be helpful in estimating blood alcohol concentration (BAC) or breath alcohol concentration (BrAC), but the results of the SBR must be interpreted more conservatively than suggested by the authors.
Methods
The original study was funded by the National Highway Traffic Safety Administration (NHTSA) and carried out in the San Diego area by seven police officers who administered the SFSTs on those stopped for suspicion of driving under the influence (DUI) of alcohol. The officers were instructed to carry out the SFSTs on the subjects, and then to note an estimated BAC based only on the SFST results: including the walk and turn (WAT), the one leg stand (OLS) and the horizontal gaze nystagmus (HGN) tests. Subjects driving appropriately were not stopped or tested. However, “poor drivers” were included because they attracted the attention of the officers. The data
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collection did not include body weight, presence of prior injuries, and other factors that might influence either the SFSTs or the measured BAC (7, 8).
The officers were asked to estimate the BAC values1 using SFSTs. Some of the subjects were arrested and given a breath test. The criteria used by the officers for estimation of BAC were not described in the report. There appears to be no specific quantitative combination of the FSTs, but rather there appears to be a subjective estimate of BAC. In other words, the decision to determine an estimated BAC was left to the subjective judgment of each officer. Each set of FSTs (for a given subject) was scored by only one officer. So it was not possible to assess inter-officer variability.
The data of Stuster and Burns were obtained via a request to the National Highway and Transportation Safety Administration (NHTSA) using the Freedom of Information Act (FOIA). Figure 1 shows the raw data {estimated BAC (EBAC) vs. measured BAC (MBAC)} for 297 subjects, who had a mean EBAC and MBAC of 0.117% and 0.122%, respectively. The figure shows the line of identity (EBAC = MBAC) and a least-squares regression line for EBAC vs. MBAC. In some cases the EBAC was greater than the MBAC resulting in a greater probability of arrest than if the MBAC had been used (points above the line of identity). In other cases EBAC was lower than MBAC resulting in a lower probability of arrest than if MBAC had been used
1 The SFSTs are designed to estimate the blood alcohol concentration (BAC) in units of gm/dl. However, the SFSTs are evaluated with the breath alcohol concentration (BrAC) in units of gm/210L. We will use the term, BAC and express the values with units of % to be consistent with the original study.
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(points below the line of identity). EBAC is plotted against MBAC for all observations. The MBAC of these points varies over a range of BAC = 0.00% to 0.33%.
Statistical Methods
The accuracy with which officers classified drivers as having a BAC above or below 0.08% is presented graphically by sorting the data on increasing MBAC and then using a moving window of 21 observations, shifting upward one observation at a time. The accuracy is calculated as the percentage of observations in the window that are correctly classified as < 0.08% or = 0.08% MBAC. The accuracy for the group of 21 observations in the window is plotted vs. the mean of the MBAC measurements in the window.
Four traditional test evaluation statistics were also calculated, namely, 1) sensitivity (percent of true positives who are correctly classified as such by the test), 2) specificity (percent of true negatives who are correctly classified as such by the test), 3) positive predictive value (percent of those with a positive test result who are true positives), and 4) negative predictive value (percent of those with a negative test result who are true negatives) (9). These test evaluation statistics are more commonly used than the accuracy measure defined by SBR. However, the term “accuracy” is used in related literature and in legal proceedings, and, therefore, we use it in this article along with the four more traditional test statistics. It is important to note that one may have very high accuracy yet have much weaker performance on one or more of the four traditional statistics, as happened with SBR.
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The relationship of MBAC with the three sub-tests of the SFST, with the total SFST score, and with EBAC were analyzed using simple and multivariate linear regression and with Pearson correlation coefficients as a descriptive measure. (10)
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Results
The accuracy of the SFST is not a single percentage, but depends very much on the level of MBAC. Using the 21-observation moving window, the accuracy of classifying individuals as above or below 0.08% MBAC can be pictured in relation to measured breath alcohol concentration (Figure 2). The data show that the officer’s accuracy in estimating whether a person’s BAC is over or under 0.08% depends on the MBAC. If MBAC is lower than 0.04, the officer is generally 80% or more accurate at predicting a subject’s category (above or below 0.08% MBAC) in the sample studied. If the MBAC is greater than 0.09%, then the officer is about 90% or more accurate at predicting the subject’s category. However, if the MBAC is around 0.08%, specifically, between 0.06 and 0.08, the SFSTs are only about 30-60% accurate in correctly predicting whether a subject’s MBAC is = 0.08% or < 0.08%. The minimum accuracy in Figure 2 is 33%.
The data also provide evidence that the officers’ estimates were not based only on the SFST. This is shown by an analysis where even very liberal use of only the SFST in a predictive model yields a BAC estimate with precision that is substantially inferior to the precision of the officers’ estimates, even though the officers were instructed to base their estimates only on the SFST.
Specifically, regression models provide a method to estimate MBAC based only on the three tests in the SFST. A regression model was fitted to predict MBAC from
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independent variables including linear and quadratic (squared) terms in the three tests: HGN, HGN2, OLS, OLS2, WAT, and WAT2. The model is liberal in using the three tests, because not all of the variables add significantly or substantially to prediction of the MBAC. Nevertheless, all variables were retained (yielding an over-fitted model), in order to maximize use of the tests within this sample, attempting to mimic or even improve on how an officer might combine test results in practice. Interaction terms between tests were also tried (e.g., HGN*WAT), but they added so little to prediction of MBAC, with a negligible increase in R-squared, that they were not used in the liberal model. (A more appropriate regression model is presented later.)
The amount of variation in MBAC explained by the model based on the three tests alone (and their quadratic terms) is 56%, which increases to 76% when EBAC (the officer estimate of BAC) is added to the model, in addition to the tests. The gain in precision in predicting the quantitative value of MBAC from the model based only on tests to the model based on the tests plus the officer estimates is statistically very significant (20% increase in R-squared, p < 0.001). The mean absolute difference between the officer estimate, EBAC, and the measured value, MBAC, is 0.024% (in BAC units), versus a larger value of 0.031% indicating less precision, for the mean absolute difference between the model-based estimate and the MBAC.
The striking increase in precision when the officer estimates are added to a liberally-fitted model using only the tests suggests that the officers did not base their estimate solely on the test scores but most likely used other clues. This suggests that
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it may be impractical to evaluate the three tests in isolation from other non-test clues used by the officers, such as slurred speech, odor of alcohol, appearance, admitted drinking or driving behavior. Another explanation may be the presence of other drugs in addition to alcohol. Or, as suggested by critics of the study, Price and Cole (9), it may be that the officers used portable breath testers (PBT) prior to recording their BrAC estimate and were then influenced by the known PBT values. The Stuster and Burns report (1, page 10) notes that “all police officers participating in the study were equipped with NHTSA-approved, portable breath testing devices to assess the BACs of all drivers who were administered the SFST…”.
The utility of individual tests (HGN, OLS and WAT) and the combination of tests to predict MBAC can be evaluated by plotting MBAC against the total score from the individual tests. Figure 3 shows a plot of the measured breath alcohol concentration versus the total score from the three tests, with a reference line at MBAC = 0.08%. For Figure 2 only, a small amount of “jitter” (random noise) has been added to the score of each subject to avoid overlapping points. The jitter is less than ±0.25 points horizontally. The considerable variation in MBAC above each point score is apparent, and in addition, for total scores 4-18, there are MBAC values lying on both sides of the 0.08% cut-point. In order to be 95% confident that the subject has a MBAC greater than 0.08%, the total score (HGN + OLS + WAT) must exceed approximately 17 (based on the 95% lower confidence limit for predicted MBAC for an individual from the regression of MBAC on total score).
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Figure 4 shows the percentage of measured breath alcohol concentration values that are above 0.08% in relation to each of the three individual test scores. For each score (horizontal axis), the percent of subjects with that score or higher who have an MBAC larger than 0.08% is plotted (Y-axis). In order to observe 95% of persons with MBAC > 0.08% in this sample, the score for WAT (circles in the plot) must be 5 or larger. None of the scores for HGN (crosses) reach the 95% point and the scores for OLS (triangles) reach over the 95% point only at 10 points and higher, where there are only two subjects. Note that the “failure” scores for these three tests, as specified by Stuster and Burns, are 4 for HGN, 2 for OLS, and 2 for WAT (12). Failure of an FST according to NHTSA standards simply estimate the 50% likelihood that a subject is > 0.08%. The data show that in order to be considerably more confident that the subject is above 0.08%, the scores should be much higher than the “failure” scores.
The correlation coefficients for individual tests vs. both MBAC and EBAC are shown in Table 1. The FST with the strongest correlation with MBAC is HGN followed by WAT and OLS. The strongest correlation is with the total test (determined by summing the scores for the three FSTs. However, total score and HGN have very similar correlations with MBAC and EBAC.
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Discussion
Figure 5, redrawn from Figure 4 of SBR. illustrates the logic used by Stuster and Burns to describe the accuracy of SFST. A correct decision was registered if both MBAC and EBAC are = 0.08% (upper, right quadrant; N=210) or both are “0.08% (lower, left quadrant; N=59). An incorrect decision occurred with a false positive (upper, left quadrant; N=24), when (EBAC = 0.08% and MBAC < n=”4),” mbac =” 0.08%.” n =” 214″> 0.12, Stuster and Burn’s conclusion that the tests have 91% accuracy was strongly affected by the fact that a majority of points are in this high MBAC range, where correct classification as above
0.08 is more reliable. Of the correct results, 210 data points out of a study total of 297 were in the 0.08% to 0.33% range and 59 were in the 0.000% to 0.079% range. (The accuracy estimated by Stuster and Burns as 91% was calculated from the values in Figure 2 as (210 + 59)/297 = 0.91). The number of false positives (N=24) was much greater than the number of the false negatives (N=4). In the range of data near the 0.08% level, the estimated BAC by these experienced officers overestimates the measured BAC, introducing a bias against the subjects (see Figure 1). Using EBAC to determine whether the subject MBAC is greater than 0.08% is 100% accurate for all subjects with MBAC > 0.12%. In other words, if the subject is highly intoxicated, the SFST provide an accurate indication. It is not surprising that if the subject is clearly intoxicated, the officers can make this determination. If the MBAC is < 0.08%, there is a 24 / (24 +59) = 29% chance of a false arrest (determined from Figure 2). 12
To illustrate the problem with the SBR statistical strategy, let’s apply the same logic to determine the level of accuracy at hypothetical cut-point (“legal limit”) levels lower than 0.08%. For example, if Stuster and Burns were to use the same data set to examine the accuracy at lower threshold BAC (0.07% down to 0.01%) levels, they would determine an increasing accuracy level at lower threshold levels. The relative increase in apparent accuracy with decreasing BAC threshold is shown in Table 2, which indicates a hypothetical cut-point for designating a driver as “over the limit”. For example, if the legal limit were 0.04%, the SBR method would conclude that SFST are 93.9% accurate. At a legal limit of 0.01%, the SBR conclusion would be that the SFST are 99.3% accurate. The method used by Stuster and Burns has determined a high degree of accuracy simply because most of the data points are at MBACs much greater than the cut-point of 0.08% used in their study. What underlies this problem is the weakness of “accuracy” as the sole performance statistic for this test, as well as the specific nature of this sample, weighted heavily toward individuals with high levels of MBAC.
An alternative way to explore the accuracy of SFST is to assess the accuracy over a range of points that is symmetric about the 0.08% cut-point (limit). In addition to accuracy, four traditional statistics of test performance also help in this exploration: sensitivity, specificity, positive predictive value and negative predictive value. Table 3 shows the accuracy of SFST when the range of interest extends above and below 0.08% by the same amount, along with the four traditional performance statistics. For
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data with MBAC ranging between 0.07% and 0.09%, The SFST are 72.2% accurate. As the range broadens, the calculated apparent accuracy increases. At the broadest range of 0.04% – 0.12%, the calculated apparent accuracy is now 82.2%. Taken to the extreme, using all of the data points (MBAC = 0.00% to 0.033%), the apparent accuracy is 91% as calculated by Stuster and Burns. The accuracy of SFST in the vicinity of 0.08% is poorer than estimated in the SBR for the whole data set.
Parallel with the reduced level of accuracy in the range 0.07-0.09% MBAC, the four traditional test performance statistics in Table 3 also show varying performance in this range. Specificity is low (36%), indicating that a large fraction of subjects (64%) would be falsely declared over the limit. The sensitivity is excellent in this range, 96%, due to the tendency of EBAC to overestimate alcohol level compared to MBAC. Positive predictive value (PPV) is fair, 70%, indicating that 30% of the subjects declared over-limit would not be so. Negative predictive value (NPV) is good, 83%, indicating that most of those declared under-limit would really be so, but this, again, due to the over-estimation by EBAC. As the range of MBAC in Table 3 steadily widens to finally include all cases, specificity increases to a maximum of only 71%, while sensitivity, PPV and NPV all reach at least 90%, due to predominance in this sample of high levels of measured alcohol.
A closer examination of the data between 0.04% and 0.12% is shown on Figure 6 (by expanding a section of Figure 1). Another way of determining the officer’s accuracy in estimating the BAC is to compare the fraction of observations (EBAC)
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overestimating and underestimating the MBAC. If we consider three ranges of MBAC, 0.00% = MBAC <> 0.10%, 50 are overestimates and 108 are underestimates of MBAC. Thus, the experienced officers used in this study tended to overestimate the BAC at low levels (<> 0.10).
The optimal predictive capability of the SFST depends on the scaling for the particular test and the predictive capacity of the test. The maximum scores permitted for HGN, OLS and WAT are 6, 4, and 8, respectively. However, some officers assigned scores that were greater than the maximum score allowable for a given FST. The highest scores assigned in this study were 6, 12, and 9 for the HGN, OLS and WAT, respectively.
By adjusting the weight given to each test and taking account of the precision of the test in predicting MBAC, we find the following linear regression model (equation 1)
15
maximizes the precision of the SFST for estimating MBAC, using only linear versions of the three test variables. The quadratic terms (squared values of the three test variables), while statistically significant as a group (p = 0.004) increase R-squared by only 2%, from 54% to 56%, and have been omitted for parsimony. The model is based on the 261 cases without any missing values for the three tests. Note in the equation below that the increase in BAC per point increase in the score is largest for HGN, with a 0.017 increase in BAC, on the average, for each point increase in the HGN score.
MBAC = -0.007 + 0.017 x (HGN Score) + 0.0012 x (OLS Score) + 0.011 x (WAT Score) (Eq. 1)
The equation does quite well in predicting the mean MBAC, but there is still a large spread of individuals around the predicted value. The standard deviation of individual MBAC values around the predicted regression value is 0.044%. A 95% confidence interval for the true MBAC of an individual, predicted from this regression model, would have a minimum width of ± 0.09%, certainly a wide range.
Using the predictors (HGN, OLS, WAT), the additive model from equation 1 accounted for 54% of the variability in MBAC (corresponding to a correlation of 0.73). Including EBAC as an additional predictor in the model resulted in a substantial and significant increase (p < 0.001) in the variance of MBAC explained, increasing it to 75%. As noted earlier, this marked increase in predictability of MBAC by adding in the
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officer’s EBAC indicates that the officers’ estimates were probably influenced by factors other than the three FSTs
We believe that the accuracy of the SFST can be improved if a weighted sum of scores from the three standard tests is combined as described in Equation 1. However, this relationship should be tested in a variety of populations, and, in a larger sample, it is possible that non-linear and other functions of the test scores may help in prediction. The evaluation should include an assessment of accuracy and bias in estimating the numerical BAC and, as well, the accuracy in classifying individuals above or below specified limits (such as 0.08%) for various low, medium and high levels of measured BAC. In follow-up trials of the FST, the instructions given to officers for converting test scores into estimates of BAC should be stated more explicitly (such as using equation 1 above, or another algorithm). Further, some attempt should be made to identify and incorporate (or control) other factors, aside from the SFST scores, that influence BAC estimates. It may be difficult or impossible to “turn off” other cues that officers use in estimating BAC or in making a decision about an arrest.
The magnitude of the correlations between the tests and MBAC suggests that this type of testing could be developed further, either through re-formulation of the tests, or through different scoring systems, or by other means. In the current framework, the test scores have to be quite high to provide confidence that the subject is above 0.08%, but further development could potentially improve confidence in the three test results, both singly and in combination. And, anticipating the possibility that
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some jurisdictions may now or in the future have lower (or higher) legal limits than 0.08%, testing could include more representation from lower levels of BrAC.
The SFST total score and sub-test scores are undoubtedly correlated with breath alcohol level (Table 1). However, predicting a numeric blood alcohol concentration from the SFST scores, as the SFST methodology is defined in the Stuster and Burns report, has limited accuracy and precision. The evidence for this is a) considerable over- and under-estimation of MBAC (see Results section); b) a large range of observed MBAC values corresponding to any given total SFST score (Figure 3); and, c) a large spread of observed MBAC values around predicted MBAC values from a liberal regression model that attempts to optimize the use of the SFST, yet has a minimum prediction uncertainty of ±0.09%.
If our interest is not in quantitative prediction, but in classifying individuals, such as below vs. equal to or above a limit of 0.08%, the utility of the SFST depends very much on how intoxicated an individual is. Accuracy (and specificity) are low when individuals are close to 0.08% MBAC (Figure 2 and Table 3), but if the individuals are quite intoxicated, such as above 0.12%, then accuracy is high (Figure 2).
The use of a single test performance statistic, accuracy, and the calculation of this one statistic for the entire study sample is an over-simplification of the more complex relationship between the SFST score and the MBAC level.
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SFSTs could become more useful if much more data are accumulated and analyzed using statistical methods such as those presented in this paper, including some of the traditional test evaluation statistics. It is likely that the usefulness of SFSTs will be greatest for drivers who have high test scores. The moderate to strong correlations between the tests and MBAC suggest a potential for further test development. Enhanced understanding would come from tests applied to a more diverse population sample as well as from the development of a statistical approach to predicting the probability of a subject having a BAC greater than 0.08 % from a particular set of SFST scores.
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References:
1. Stuster J, Burns M. Validation of the standardized field sobriety test battery at BACs below 0.10 percent. August, 1998. National Highway Traffic Safety Administration. 2. Burns M, Moskowitz H. Psychophysical tests for DWI arrest. Technical Report DOTHS-5-01242. National Highway Traffic Safety Administration. Washington, DC. 3. Tharp V, Burns M and Moskowitz H. Development and field test of psychophysical tests for DWI arrest. US Department of Transportation, National Highway Traffic Safety Administration Final Report DOT-HS-805-864, Washington, DC. 4. McKnight, AJ, Langston, EA, McKnight AS, Lange, JE. Sobriety tests for low blood alcohol concentrations. Acc Anal & Prevent 2002;34: 305-311. 5. Heishman, SJ, Singleton, EG, Crouch, DJ. Laboratory validation study of drug evaluation and classification program: ethanol, cocaine, and marijuana. J Anal Toxicol 1996; 20: 468-481. 6. Cole S and Nowaczyk, RH. Field sobriety tests: Are they designed for failure? Perceptual and Motor Skills 1994; 79: 99-104. 7. Hlastala M. The alcohol breath test – A brief review. J Appl Physiol 1998; 84: 401408. 8. Hlastala M. Invited editorial on “The alcohol breath test”. J Appl Physiol 2002; 93: 405-406. 9. Price P, Cole S. NHTSA field sobriety tests validation v. invalidation, 25 The Champion. 2001; 25: 37-42. 10.Fisher LD, van Belle G. Biostatistics. Wiley, 1993. 11.Weisberg S. Applied linear regression, 2nd edition. Wiley, 1985. 12.NHTSA DWI Detection and Standardized Field Sobriety Testing Student Manual, DOT-HS-178-R1/02.
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Additional information and reprint requests:
Michael P. Hlastala, Ph.D. Division of Pulmonary and Critical Care Medicine, Department of Medicine Department of Physiology and Biophysics Box 356522 University of Washington Seattle, WA 98195-6522 Email: hlastala@u.washington.edu
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TABLES
Table 1. Pearson correlation of three Field Sobriety Tests with measured breath alcohol (MBAC) and officer-estimated breath alcohol (EBAC).
TEST MBAC EBAC TOTAL score (3 tests) 0.69 0.74 HGN Horizontal Gaze Nystagmus 0.65 0.71 WAT Walk and turn 0.61 0.64 OLS One leg stand 0.45 0.51
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Table 2. Accuracy of “over-limit” designation based on estimated breath alcohol concentration for defined cut-points (hypothetical legal “limit”) of measured breath alcohol concentration (MBAC)
Legal “limit” (%) N: All N: MBAC < cut-point N: MBAC ! cut-point Accuracy* 0.10 297 107 190 90.6% 0.09 297 97 200 89.2% 0.08 297 83 214 90.6% 0.07 297 69 228 89.6% 0.06 297 58 239 90.6% 0.05 297 43 254 92.3% 0.04 297 29 268 93.9% 0.03 297 19 278 93.9% 0.02 297 9 288 97.6% 0.01 297 4 293 99.3%
*Accuracy = 100%*(# correctly classified as ! limit or < limit)/total
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Table 3. Accuracy and other statistics related to “over-limit” designation based on estimated breath alcohol concentration for defined ranges of MBAC.
Range of MBAC Total in Range Accuracy Sensitivity Specificity PPV NPV 0.07 – 0.09 36 72% 96% 36% 70% 83% 0.06 – 0.10 65 75% 95% 44% 73% 85% 0.05 – 0.11 97 79% 97% 55% 75% 92% 0.04 – 0.12 135 82% 95% 63% 79% 90% All cases 297 91% 98% 71% 90% 94%
Accuracy = (# correctly classified as ! 0.08 or < 0.08)/total PPV = positive predictive value NPV = negative predictive value
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Figure Legends:
Figure 1. Estimated BAC vs. Measured BAC for all subjects in the Stuster and Burns study. The line of identity (Estimated BAC = Measured BAC; thin line) and linear regression line (heavy solid line) are shown.
Figure 2. Accuracy of classification of individuals as ! 0.08% or < 0.08% MBAC using the officer estimate. Accuracy is plotted vs. measured breath alcohol concentration (horizontal axis).
Figure 3. Measured breath alcohol concentration versus total of three test scores.
Figure 4. Percent of subjects with MBAC greater than 0.08% vs. the individual test score, with the percentage calculated for all individuals at or above the designated score.
Figure 5. Decision matrix at 0.08% BAC (modified from figure 4 in Stuster and Burns).
Figure 6. Data from Figure 1 expanded to show points between 0.04% and 0.12%. The line of identity (EBAC = MBAC), dashed line and linear regression line (heavy solid line) are shown.
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Figure 1
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Figure 2
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Figure 3.
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Figure 4.
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30 Figure 5. Measured BAC (MBAC) Estimated BAC (EBAC) < 0.08% ! 0.08% < 0.08% ! 0.08% N=24 N=210 N=59 N=4 Figure 6.
31

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Are Standardized Field Sobriety Test Designed for Failure?

January 8, 2007 by alabamadui

Perceptual and Motor Skills, 1994, 79, 99-104. 8 Perceptual and Motor Skills 1994

FIELD SOBRIETY TESTS: ARE THEY DESIGNED FOR FAILURE?’

SPURGEON COLE AND RONALD H. NOWACZYK

Clemson. University

Summary–Field sobriety tests have been used by law enforcement officers to identify alcohol-impaired drivers. Yet in 1981 Tharp. Burns. and Moskowitz found that 32.% of individuals in a laboratory setting who were judged to have an alcohol level above the legal limit actually were below the level. In this study, two groups of seven law enforcement officers each viewed videotapes, of 21 sober individuals performing a variety of field sobriety tests or normal-abilities tests, e.g.. reciting one’s address and phone number or walking in a normal manner. Officers judged a significantly larger number of the individuals as impaired when they performed the field sobriety tests than when they performed the normal-abilities tests. The need to reevaluate the predictive validity of field sobriety tests is discussed.

Field sobriety tests have been used throughout this century by police officers to help them assess whether an individual is too impaired to drive an automobile. A classic paper by Bjerver and Goldberg, (1951) examined the relationship between performance on the field sobriety test and driving. Over the past two decades the National Highway Transportation Safety Administration (NHTSA) has funded several studies to examine the effectiveness of field sobriety tests in predicting a person’s level of intoxication and driving impairment (e.g., Anderson. Schweitz. & Snyder. 1983; Burns & Moskowitz. 1977; Tharp, Burns, & Moskowitz. 1981).
In a 1977 report, Burns and Moskowitz examined a number of different tests commonly used by officers. Based on the results from a laboratory study, they recommended three tests, the Horizontal Gaze Nystagmus (HGN) test, the walk-and-turn test, and the one leg stand test for further research. The HGN measures the angle of gaze at the onset of jerking movement which can be influenced by alcohol consumption as well as other physiological factors. The other two tests require dividing, attention among mental and physical tasks. Briefly, the walk-and-turn test requires a person to stand on a line in a heel-to-toe position while listening to instructions and then to take nine steps in a heel-to-toe fashion, pivot, and take nine more steps along a straight line. The one-leg stand requires an individual to stand with arms at the side and extend one foot six inches off the ground and maintain that position while counting for 30 seconds without extending the arms or losing balance. (For complete instructions see “DWI Detection and

‘Requests for reprints can be sent to either author at the Department of Psychology, Clemson University, Clemson, SC 29634. The authors thank Ronnie Cole for his assistance in the completion of this study and Jack Davenport for his comments on an earlier draft of this manuscript.
100 S. COLE & R.H. NOWACZYK

Divided Attention Field Sobriety Testing” by NHTSA, 1987.) Although these tests seemed to hold the most promise, the authors reported that false alarms are a concern. In the 1977 study, 47 percent of the subjects who would have been arrested based on test performance actually had a blood alcohol concentration (BAC) lower than .10 percent, the decision level used by officers.
A 1981 report by Tharp, et al employed the three previously mentioned tests in another laboratory study. The error rate improved somewhat; 32 percent of the participants judged to have BACs greater than .10 actually had BACs lower than .10, the decision point used in many states for assuming driving impairment. Reliability coefficients for these tests, however, were often below accepted levels for standardized clinical tests. Reliable rests have coefficients of approximately .85 or higher (Rosenthal & Rosnow, 1991). Test-retest reliability coefficients for the field sobriety tests ranged from .61 to .72 for individual tests and .77 for the total test score for 77 individuals who were dosed to the same BAC level on two occasions. Interrater reliability coefficients, based on having different officers score performance on each occasion, were even lower, ranging from .34 to .60 with .57 as an over-all test score.
Problems in scoring can be attributed, in part, to the lack of standardization across many of the field sobriety test studies. In addition, a few miscues in performance can result in an individual being scored as impaired (Anderson, et at.. 1983). For example, a person is viewed as impaired for missing two of nine points on the walk-and-turn test or two of five points on the one-leg stand test. The stringent scoring criteria as well as potential subjectivity in determining whether a point should be awarded may account for accuracy rates that vary from 72 to 96 percent among police agencies using these tests in the Anderson, et al. study. The fact that these tests are largely unfamiliar to most people and not well practiced may make it more difficult for people to perform them. As few as two miscues in performance can result in an individual being classified as impaired because of alcohol consumption when the problem may actually be the result of their unfamiliarity with the rest.
This study tested the hypothesis that sober individuals will find the field sobriety tests difficult to perform and, as a result, will be judged to be impaired by officers viewing their performance. Individuals who were completely sober were asked to perform several field sobriety tests and several “normal-abilities” tests which should be well known to individuals. These latter tests included answering personal data questions, such as stating one’s address and phone number, as well as walking in a normal manner. Performance on the field sobriety tests and normal-abilities tests was videotaped. Law enforcement officers were asked to view these tapes and deter-
FIELD SOBRIETY TESTS 101

mine if these individuals were impaired (“too drunk to drive”). If the field sobriety tests are difficult to perform under normal circumstances, then we can expect officers to judge incorrectly individuals as being impaired on the basis of the field sobriety test performance as compared with scores on the normal-abilities tests.

METHOD
Subjects and Design

Fourteen police officers from the local municipality or county sheriff’s office rated the performance of 21 individuals who had completed the field sobriety and normal-abilities tests. These officers, with 1 to 17 years of law enforcement experience (M = 11.7 yr.) were volunteers who were certified by the South Carolina Academy for Police Officers which is a state requirement. As part of this certification requirement they had completed the state DUI training program and have had field experience with DUI detection. All officers were assigned to duties in the field.
Ten males, seven white and three African-American. and eleven white females served as participants. They were recruited from local businesses. The owners of these businesses were asked if they had any employees who were willing to volunteer to serve in an experiment involving psychomotor tasks. Participants were currently employed, between 21 and 55 years of age, and not overweight, and had no known physical disabilities.
All individuals and officers were paid for their participation. The individuals performed both field sobriety tests as well as normal-abilities tests. Half of the officers were randomly assigned to each condition in which they viewed performance on either the field sobriety or normal- abilities tests.

Tests Performed

Prior to the administration of the tests, each participant was administered the Datamaster breathalyzer test. All participants had a BAC level of .00. Each participant performed six field sobriety tests and four normal-abilities tests in the same order in an indoor setting. The field sobriety tests included the walk-and-turn test, alphabet recitation, one-leg stand, a one-leg stand while tilting backward with the eyes closed and touching the nose, a one-leg stand with counting, and a one-leg extension test. These tests were selected after interviewing a number of officers concerning tests they used in the field. None of these officers served in this study. The Horizontal Gaze Nystagmus test was not included because it requires officers individually to monitor the participants’ eye movements which would have been difficult to videotape in a controlled fashion. It is also not included in the 1987 NHTSA self-instructional guide (NHTSA, 1987). The four normal-abilities tests included counting from 1 to 10, reciting one’s Social Security number, driver’s license number or date of birth, recit-

102 S. COLE & R. H. NOWACZYK

ing one’s home address and phone number, and walking in a normal manner, turning around, and walking back to the starting point. These tests were selected by the experimenters to sample motor and cognitive activities that are commonly performed by most individuals.
Standard instructions for each test were read by the experimenter. Participants were told that they would perform a number of motor-coordination tasks that would last approximately 30 minutes. These instructions were based on those used by law enforcement in South Carolina and followed NHTSA guidelines. If participants had questions regarding the instructions, the experimenter reread the appropriate section. The reading of instructions was included on the videotape. The tests were performed indoors in a meeting room where distractions were minimal. A 7.62-cm wide strip of tape was placed on the floor for the walk-and-turn test as per NHTSA requirements.

Procedure

Each officer watched a videotape of the 21 individuals performing one of the two sets of tests. The order of performance of the individuals was the same for both the field sobriety tests and normal-abilities tests. The officers were provided with sheets of paper listing the participants by number. The officers were allowed to take notes and were asked “Do you fee!, as a law enforcement officer, that the following subjects, based on field sobriety tests performed on videotape, have had too much to drink to drive.
Their responses, either “yes” or “no,” were recorded for each individual. The decision was recorded by the officer immediately, after viewing the individual’s performance and prior to viewing the next individual’s performance. Eachofficer participated in individual sessions.

RESULTS
The proportion of officers who decided that an individual had “too much to drink” was recorded for each individual separately for the field sobriety and normal-abilities tests. There was a significant difference as a function of test (t29 = 4.38, p<.01). Forty-six percent of the officers’ decisions were that an individual had “too much to drink” from viewing the field sobriety tests. Fifteen percent of the decisions from the normal-abilities tests were that a person had “too much to drink.”
Differences among individuals were apparent. Only three individuals were rated as “unimpaired” by ail officers on both the field sobriety and normal-abilities tests. One individual’s performance was rated as showing he had had “too much to drink” based more on the normal-abilities tests (by three officers) than on the field sobriety tests (none of the officers). Five individuals were rated as having had “too much to drink” by all the officers who viewed the field sobriety tests. One other individual was rated as having had “too much to drink” by all but one officer. Of these six individuals

FIELD SOBRIETY TESTS 103

only one was rated as “impaired” by as many as four of the officers who saw the same individuals performing the normal-abilities tests. Four of these individuals were rated as having had “too much to drink” by two or fewer of the officers viewing the normal-abilities tests.

Discussion

The data indicate that judgments of impairment are influenced by the type of test performed. An individual was more liken to be judged as impaired on the basis of field sobriety test performance than on performance of the normal-abilities tests. Even without alcohol, the number of errors made by individuals performing the field sobriety tests was sufficient for officers to judge that the individuals had had too much to drink. These findings are consistent with other studies reporting sizable percentages of individuals judged to be impaired when they were not (Burns & Moskowitz, 1977; Tharp, et al, 1981).
While training of officers, standardization of test instructions, administration, and scoring may reduce the number of incorrect classifications, the major obstacle may be the field sobriety tests. The fact that these tests require unfamiliar and unpracticed motor sequences may put an individual at a disadvantage when performing them. To the law enforcement officer who has demonstrated the tests many times, the motor sequences may, seem easy and straightforward. It may also be that to the casual observer that the tests are easy to perform. Yet, when an untrained individual actually performs the test, then the difficulty of performing the tests at an acceptable level may become evident.
The reliance on field sobriety test performance by law enforcement officers in their decision to arrest or not and by juries in their decision whether to convict a person of driving under the influence underscores the need to examine field sobriety tests critically. The tests should discriminate between the two populations of individuals who are impaired and those who are not. Ideally, the tests should separate the two populations, that is, increase d, the mean difference between the two populations. The tests, however, may be doing nothing more than adjusting the officer=s β, or criterion measure, downward.
These tests must be held to the same standards the scientific community would expect of any reliable and valid test of behavior. This study brings the validity of field sobriety tests into question. If law enforcement officials and the courts wish to continue to use field sobriety tests as evidence of driving impairment, then further study needs to be conducted addressing the direct relationship of performance on these and other tests with driving. To date, research has concentrated on the relationship between test performance and BAC and officers’ perceptions of impairment. This study indicates that these perceptions may be faulty.

104 S. COLE & R. H. NOWACZYK

REFERENCES

Anderson, T. E., Schweitz, M. B (1983) M. B. (1983) Field evaluation of a behavioral battery for DWI. Final Report, DOT-HS-806476.

Bjerver, K. &: Goldberg, L. (1951} Effect of alcohol ingestion on driving ability: results of practical road tests and laboratory experiments. Quarterly Journal of Studies on Alcohol, 11, 1-30.

Burns, M., & Moskowitz, H. (1977) Psychophysical tests for DWI arrest. Final Report, DOT-HS-802-424, NHTSA. ‘

NHTSA. (1987) DWI Detection and Divided Attention Field Sobriety Testing. Final Report, DOT-HS-807-186.
Rosenthal, R., &: Rosnow, R. L. (1991) Essentials of behavioral research methods and data analysis. (2nd ed.) New York: McGraw-Hill.
Tharp, V., Burns, M., & Moskowitz, H. (1981) Development and field test of psychophysical
tests for DWI arrests. Final Report, DOT-HS-805-864, NH’ISA.

Accepted May 23. 1994.

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Chemical Test for Intoxication

January 8, 2007 by alabamadui

Section 32-5A-194

Chemical tests; admissible as evidence; procedure for valid chemical analyses; permits for individuals performing analyses; persons qualified to withdraw blood; presumptions based on percent of alcohol in blood; refusal to submit; no liability for technician.

(a) Upon the trial of any civil, criminal or quasi-criminal action or proceeding arising out of acts alleged to have been committed by any person while driving or in actual control of a vehicle while under the influence of alcohol or controlled substance, evidence of the amount of alcohol or controlled substance in a person’s blood at the alleged time, as determined by a chemical analysis of the person’s blood, urine, breath or other bodily substance, shall be admissible. Where such a chemical test is made the following provisions shall apply:

(1) Chemical analyses of the person’s blood, urine, breath or other bodily substance to be considered valid under the provisions of this section shall have been performed according to methods approved by the Department of Forensic Sciences and by an individual possessing a valid permit issued by the Department of Forensic Sciences for this purpose. The court trying the case may take judicial notice of the methods approved by the Department of Forensic Sciences. The Department of Forensic Sciences is authorized to approve satisfactory techniques or methods, to ascertain the qualifications and competence of individuals to conduct such analyses, and to issue permits which shall be subject to termination or revocation at the discretion of the Department of Forensic Sciences. The Department of Forensic Sciences shall approve permits required in this section only for employees of state, county, municipal, and federal law enforcement agencies and for laboratory personnel employed by the Department of Forensic Sciences.

(2) When a person shall submit to a blood test at the direction of a law enforcement officer under the provisions of Section 32-5-192, only a physician or a registered nurse (or other qualified person) may withdraw blood for the purpose of determining the alcoholic content therein. This limitation shall not apply to the taking of breath or urine specimens. If the test given under Section 32-5-192 is a chemical test of urine, the person tested shall be given such privacy in the taking of the urine specimen as will insure the accuracy of the specimen and, at the same time, maintain the dignity of the individual involved.

(3) The person tested may at his own expense have a physician, or a qualified technician, registered nurse or other qualified person of his own choosing administer a chemical test or tests in addition to any administered at the discretion of a law enforcement officer. The failure or inability to obtain an additional test by a person shall not preclude the admission of evidence relating to the test or tests taken at the direction of a law enforcement officer.

(4) Upon the written request of the person who shall submit to a chemical test or tests at the request of a law enforcement officer, full information concerning the test or tests shall be made available to him or his attorney.

(5) Percent by weight of alcohol in the blood shall be based upon grams of alcohol per 100 cubic centimeters of blood or grams of alcohol per 210 liters of breath.

(b) Upon the trial of any civil, criminal, or quasi-criminal action or proceeding arising out of acts alleged to have been committed by any person while driving or in actual physical control of a vehicle while under the influence of alcohol, the amount of alcohol in the person’s blood at the time alleged as shown by chemical analysis of the person’s blood, urine, breath or other bodily substance shall give rise to the following presumptions:

(1) If there were at that time 0.05 percent or less by weight of alcohol in the person’s blood, it shall be presumed that the person was not under the influence of alcohol unless the person was operating a motor vehicle in performance of his or her duties as a school bus driver or day care driver at that time or was under the age of 21 years at that time.

(2) If there were at the time in excess of 0.05 percent but less than 0.08 percent by weight of alcohol in the person’s blood, such fact shall not give rise to any presumption that the person was or was not under the influence of alcohol, but such fact may be considered with other competent evidence in determining whether the person was under the influence of alcohol unless the person was operating a motor vehicle in performance of his or her duties as a school bus driver or day care driver at that time or was under the age of 21 years at that time.

(3) If there were at that time 0.08 percent or more by weight of alcohol in the person’s blood, or greater than .02 percent if the person was operating a motor vehicle in performance of his or her duties as a school bus driver or day care driver at that time or was under the age of 21 years at that time, it shall be presumed that the person was under the influence of alcohol.

(4) The foregoing provisions of this subsection shall not be construed as limiting the introduction of any other competent evidence bearing upon the question whether the person was under the influence of alcohol.

(c) If a person under arrest refuses to submit to a chemical test under the provisions of Section 32-5-192, evidence of refusal shall be admissible in any civil, criminal or quasi-criminal action or proceeding arising out of acts alleged to have been committed while the person was driving or in actual physical control of a motor vehicle while under the influence of alcohol or controlled substance.

(d) No physician, registered nurse or duly licensed chemical laboratory technologist or clinical laboratory technician or medical facility shall incur any civil or criminal liability as a result of the proper administering of a blood test when requested in writing by a law enforcement officer to administer such a test.

(Acts 1980, No. 80-434, p. 604, §9-103; Acts 1988, No. 88-660, p. 1058, §1; Acts 1995, No. 95-784, p. 1862, §2; Acts 1996, No. 96-341, p. 416, §2; Acts 1996, No. 96-705, p. 1174, §2.)

Posted in Alabama DUI Statutes | 1 Comment »

ALABAMA DUI ATTORNEY BLOG

Chemical Test for Intoxication

Section 32-5A-194

Chemical tests; admissible as evidence; procedure for valid chemical analyses; permits for individuals performing analyses; persons qualified to withdraw blood; presumptions based on percent of alcohol in blood; refusal to submit; no liability for technician.

(Acts 1980, No. 80-434, p. 604, §9-103; Acts 1988, No. 88-660, p. 1058, §1; Acts 1995, No. 95-784, p. 1862, §2; Acts 1996, No. 96-341, p. 416, §2; Acts 1996, No. 96-705, p. 1174, §2.)

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