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Q: California law and forensic science. DUI testing data non-admissable. ( Answered,   0 Comments )
Subject: California law and forensic science. DUI testing data non-admissable.
Category: Science > Chemistry
Asked by: disenfranchised-ga
List Price: $200.00
Posted: 17 Apr 2006 18:38 PDT
Expires: 17 May 2006 18:38 PDT
Question ID: 719972
This is a real situation.  An individual was re-directed (for
speeding) by the California Highway Patrol, off the highway and on to
an active working 'dairy farm.'  The individual (male 60 years old) was
?asked? to get out of the car and subject himself to a ?road side test
for alcohol consumption.? The smell of methane gas (from the cows and
standing manure) was very strong in the air. There were upwards of 200
milking cows standing within 100 feet of the individuals testing
position.  The patrolman, determining sobriety, administered several
breath tests over a 45 minute period. The individual, wearing gym
shorts, informed the patrolman that he was exceptionally cold and was
severely shivering.  It was cold (37 degrees), dark and near 5:00 PM
in November. The individual was instructed to over and over again to
inhale deeply, and then ordered to fully exhaust all the air into the
testing devices. The tests registered, following several readings,
officially at .07 (the legal limit in California) with some readings
slightly higher.  The individual, having no priors and a perfect
driving record, nevertheless, was arrested, handed over to the jailer as ?very
cooperative and sober? then later booked. The individual is represented by
counsel and wants the District Attorney to the drop charges so as to
avoid trial and/or a DUI on his driving record.  Question is: 
Forensically, was the testing (as described) a fair test knowing that
methane gas contains and yields ethanol (ethanol is the alcohol of
beer, wines, and liquors)? Clearly, there are factors and the testing
environment was compromised as the individual inhaled certain levels
of methane/ethanol gases. Would California testing equipment be
impacted? The individual seeks introduction/delivery of any known ?cases,
decisions, facts or situations,? which substantiates, that the testing as
described, and if so entered in a California court of law, would
expectedly be deemed unreliable and thus non-admissible evidence?  In
summary, the individual seeks specific and convincing data, from qualified
sourcing, of which can be presented to the District Attorney thereby
convincing the District Attorney, and his staff, to dismiss DUI
charges for lack of evidence.
Subject: Re: California law and forensic science. DUI testing data non-admissable.
Answered By: tutuzdad-ga on 17 Apr 2006 19:51 PDT
Dear disenfranchised-ga;

Thank you for allowing me an opportunity to answer your interesting
question. I hope you don?t kill the messenger because of the message,
but I have to be honest with you about what you are seeking lest the
driver find himself in an extremely compromising position. Here goes:

Having been a member of law enforcement for more than two decades, and
(among many other specialties over the years) spending a substantial
part of that time a forensic evidence technician, I can tell up if
front that your defense theory is fatally flawed for a number of
reasons, a few of which I will outline here:

Reasonable belief: You neglected to mention the reason why the
arresting officer pulled the driver over in the first place. Obviously
his suspicious behavior and/or his poor driving ?appeared? to be
consistent with an intoxicated driver BEFORE the alleged ?alcohol? was
supposedly ?inhaled?. Undoubtedly this officer has the driver?s
inadequacies on tape to use against him in court.

The roadside sobriety test:  The questioning and dexterity tests that
are often given usually determine whether the officer should proceed
with the presumptive roadside breath test. This too will probably be
on tape. While one can explain away poor driving skills, it?s
difficult to explain unsteadiness, slurred speech, imbalance, etc.

Nystagmus:  Many law enforcement officers and paramedics are trained
to spot abnormal eye movement consistent with various forms of
intoxication. This is called the Nystagmus Test (also known as
?nystagmus gaze? or ?nystagmus deviation?). This is the rather
innocuous test you see on television when an officer instructs a
driver to ?follow my pen? or ?follow my finger? with their eyes. The
results of this test (which may also be on tape), assuming the test
was given, will carry substantial weight in the officer?s testimony.
Presumably this would also have been administered BEFORE the
?inhalation? took place in readiness for the presumptive breath test.


Presumptive testing: Contrary to popular belief, the roadside breath
test does not determine a person?s guilt or innocence; nor does it
indicate beyond a reasonable doubt if a person is intoxicated. The
device used by the police is little more than a tool to help the
officer ?presume? that a person is legally over the limit of onboard
alcohol ? in the same way that the pen is a tool in the nystagmus
test. Typically, however the roadside test can be saved and physically
presented in court to (a) back up the officer?s cause for the initial
stop, (b) corroborate the data collected from other field tests, and
(c) help confirm the data obtained from later tests forensic testing
(breathalyzer, blood alcohol testing, urinalysis, etc).


Forensic tests:  In all 50 states and territories a person who is
taken into custody for driving while intoxicated has the right to
further testing (in some states this is done at the driver?s expense).
The results from these tests will undoubtedly be used against the
driver in court. Failure to submit to further testing (usually a
calibrated breathalyzer at the police station) can result in
additional charges in most states. This too can be held against the
driver as ?prima facie? evidence that the person is guilty.


Most states require a 20-minute waiting period, during which the
suspect is observed, from the time of the stop to the time of the
Breathalyzer test, to insure that any extraneous inhaled substances
are adequately purged or that substances on the surfaces of the mouth
or throat are free of foreign material. It is important to note that
modern breath testing equipment is specifically designed to minimize
the impact of mouth alcohol, acetone, paint and glue fumes, food,
confections (breath mints, etc), methane and practically any other
substance found in the human breath. Methane, in particular, does not
react in a breathalyzer the same way that intoxicating alcohol reacts
so the defense that the high reading is a result of ambient methane is
simply a doomed effort from the outset.

Couple those facts with an observation period and the damning results
are hard to argue with. To make the manure defense even more fatal,
this observation period is commonly video taped in most jurisdictions
so the suspect cannot claim later that he or she vomited, belched, or
otherwise reacted in such as way that might interfere with an accurate
reading. If this was taped, there is also a likelihood that it will
also be presented in court to verify the test results.

Additional tests:  Finally, if the driver was truly sober and did not
take advantage of his right to immediately submit to a blood or urine
test at the facility of his choice (at his own expense), shame on him.
He missed an excellent opportunity clear himself of the charges.

Has this defense been tried before? Oh yeah?.it doesn?t work! It will
only get the driver very embarrassed:

QUESTION: ?One of my county extension agents has a client who was
stopped by a Highway Patrol Officer for a suspected DUI.  The client
failed the breathalyzer test and was charged for DUI. The client has
maintained that he had been working around a manure holding facility
at a hog farm and he had enhaled (sic) enough methane that it affected
his motor skills and exhaled breath, enough so that it caused a
positive response on the breathalyzer.  He says he is innocent of DUI.
Is this possible?  Can methane affect a breathalyzer and prompt a DUI
that is correct??

ANSWER: ?Nice try for the client, George, but this time, NO CIGAR!

Most breathalysers rely on the action of a fairly specific
dehydrogenase to convert alcohol into an aldehyde? that causes the
color reaction. Methane is not chemically changed by this process.
Further, methane has only asphyxiant biological effects since it is
relatively insoluable in aqueous fluids. At the level where you would
anticipate a reduction in ambient oxygen to less than 18%, the
concentration of methane would be above its lower explosive limit of
5% and you would anticipate that the client would have been blown out
of the hog barn long before he was partially asphyxiated.?

In my opinion the driver has at least two options (perhaps others, but
he should consult an attorney about those - tell him to feel free to
take the entirety of this answer with him when he goes.):

1.  Face the music and hope it doesn?t hurt too badly.

2.  Retain a lawyer and try to defend himself using a ?proper
procedure? defense. In this case the driver would not focus so much on
the fact that he isn?t guilty, so much as he?s try to attack the
credibility or reliability of the officer, procedure or equipment, or
the manner or order in which they were (or were not) used (or

As I said in the beginning, be gentle. I pull no punches and I
couldn?t produce what you had hoped for (because it doesn?t
successfully exist) but the truth is the truth and I suspect that you
preferred to have honesty in exchange for the money you have invested
in this question that might save this driver from a potential
conviction using this (for lack of a better term) ?lame? defense
theory, as opposed to a mere rub down full of half-witted,
misinformed, nonsense that would almost certainly lead to endless
embarrassment for him. I hope you find that my research exceeds your
expectations. If you have any questions about my research please post
a clarification request prior to rating the answer. Otherwise, I
welcome your rating and your final comments and I look forward to
working with you again in the near future. Thank you for bringing your
question to us.

Best regards;
Tutuzdad ? Google Answers Researcher


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