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DUI
Defense
Breath Test
Many people believe that breath testing is
an accurate method of determining the amount of alcohol in a person's
blood. In fact, breath testing is far from accurate and as currently
used is fraught with error which can lead to false high readings that are
significantly higher than a person's true blood alcohol content at the
time of the test or at the time of operation based upon a number of
variables not taken into account by the machine. Prior to deciding whether
or not you take the test, the arresting officer must read your
Advice of Rights.
Breath to Blood
Partition Ratios
Breath testing is based upon the principal that there is a direct
relationship between the amount of alcohol in a person's expired air
sample and the amount of alcohol in the person's blood. All breath
testing equipment currently used in the United States assumes this ratio
to be 2100 to 1. In other words; the amount of alcohol in one milliliter
of our blood when consuming alcohol is 2100 times greater than the amount
of alcohol found in 1 cubic centimeter of our expired air sample.
According to the theory, if one took 2100 cubic centimeters of our deep
lung air and analyzed the amount of alcohol in that sample, the amount of
alcohol in that sample would be equal to the amount of alcohol in one
milliliter of our blood.
 Consequently, the machines
are calibrated on the assumption that everyone has a 2100 to 1 ratio.
However, not everyone has a 2100 breath to blood ratio. In fact,
recent research shows this ratio to vary from 990 to 1 to 3005 to 1.
If a person has a ratio lower than 2100 to 1 then the corresponding breath
test result will be artificially high. On the other hand, if a
persons ratio is higher than 2100 to 1, then a persons breath test sample
will be artificially low. For example, if a person took a breath
test and produced a .08 and had a breath to blood partition ratio of 1000
to 1, the persons true blood alcohol content would be .04. Because
the machine does not have the capability to determine what a person's
actual ratio is, it has no way of detecting the error it has made.
Moreover, a person's breath to blood partition ratio varies from person to
person and even varies within the person over time, making it almost
impossible to classify the breath tests results as accurate.
In the absorptive phase, the average mean for a healthy white male is 1776
to 1. Through the use of statistical analysis this translates into
75% of the people submitting to the test being overestimated and 25% being
underestimated based upon this factor alone. The absorptive phase
can last up to 5 hours after a persons last drink on a full stomach and 2
on an empty stomach.
On the other hand, if a person is in the post absorptive phase, 25% will
be overestimated and 75% will be underestimated based upon this factor
alone. Current breath testing equipment assumes that a person is in
the post-absorptive phase when in fact many people arrested for DWI are in
the absorptive phase. Even the leading proponents of breath testing
concede that it is virtually impossible to determine at which stage a
person is in at the time of the test and therefore impossible to determine
whether or not the person is overestimated or underestimated.
Breathing
Technique
A person's breathing technique (the way a person blows into a breath
testing machine) will effect the accuracy of the reading produced on the
machine. To produce a .08 on a Intoximeter EC/IR, the machine
actually detects less than 1 millionth of a fluid ounce of alcohol in the
breath sample. This amount is smaller than a pin head. If a person
blows into the machine for a long period over 10 seconds, the resulting
reading can be higher than the person's actual true blood alcohol content
by to 150%. In a recent lecture at Harvard University, Dr. Michael
Hlastala of the University of Washington Department of Medicine confirmed
that breathing technique can significantly impact on a person's true BAC.
If a person holds their breath, or is a shallow breather, that can cause
the reading to be over 20% higher than the true BAC. Given that the
breathing pattern is not controlled, it is impossible to determine whether
or not a person's result on the breath test is artificially high and to
what degree.
Trace
Contamination
Many of today's breath testing equipment rely on infrared analysis to
determine how much alcohol is in a person's expired breath sample. A
major flaw in the analysis is that many of these instruments are
non-specific for alcohol. That is, they are not designed to detect
the molecule of ethyl alcohol, but rather only a part of that molecule -
the methyl group. These machines are based on the Baer-Lambert
theory which states that all organic substances absorb infrared energy at
different wave lengths. Alcohol absorbs at over 8 wave lengths
however, the great majority of the Intoximeter EC/IR's currently being
employed only test at two wave lengths 3.39 and 3.48 microns. This
creates a potential problem because there are several other compounds or
substances that absorb at these wave lengths that may be present in a
person's air sample. When these other substances are present, the machines
read them as being alcohol molecules when in fact they are not. This
can lead to a situation where a person is charged with DWI based upon a
breath test when in fact he has no alcohol at all in his blood. One study
conducted recently revealed a case where a cabinet maker produced a
reading of .24 when a simultaneous blood test showed that he had no
alcohol in his blood. The reading was obviously attributable to the
cabinet maker's inhalation of chemicals contained in the paint he was
applying which have a similar chemical structure of alcohol.
If a person belches, or has false teeth, this can also produce false high
readings.
Temperature
The temperature of the person's breath sample is also of importance.
If the temperature of a person's breath sample is 1 degree above 34 C,
then the person's reading will be about 7% higher than the person's true
BAC. Temperature is an important variable that should be measured
and controlled when evaluating the accuracy of any breath test however, to
date no machine has been designed to make sure the subject's breath sample
is of the proper temperature.
Complete the
FREE DUI Arrest Evaluation,
and Mr. Athen will contact you within one business day to discuss your
case.
While some law firms substitute attorneys,
(imagine walking into court to see someone that you have never
met there to represent you!) when you hire
Scott Athen to represent you in court, you get Scott Athen!
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