A successful DUI defense also involves challenging breath results.

DUI defense against breath results begins by attacking breath machines because they are not designed to read just alcohol.  This means that despite how scientific everyone claims the machines are, they cannot only specifically read ethanol, the active component of alcohol.  The more advanced devices have both a fuel cell and infrared analysis, designed to increase the machine’s reacting only to alcohol.  Such improvements are not complete; even the most sophisticated devices react to compounds other than ethanol.  A competent DUI lawyer can debunk the myth that the machine is always accurate!  It simply is not, because it cannot just read alcohol.

Regardless of the device that you used, your DUI defense can exploit other problems from which all breath machines suffer.  First, the person administering the breath tests must observe the subject for 15 minutes prior to the tests.  This observation is designed to rule out other sources of contamination, false “high” reads, such as mouth alcohol due to belching or regurgitation.

Successful DUI defense involves an analysis of the 15 minute period.  This 15 minute period of time is so critical that it has actually been legislated into a requirement until Title 17, a law governing the administration of breath tests.   The 15 minute observation period requires that police observe you for at least 15 minute before they administer a breath test.  The observation period is important to prevent any contamination of the results through the release of alcohol into the mouth by belching or regurgitation.  Police will try to circumvent this 15 minute observation period by quizzing the driver when the driver last consumed alcohol and if the driver vomited or belched during the last 15 minutes before taking the test.

But the bottom line is that the breath devices do a woefully inadequate job in detecting any mouth alcohol.  This 15 minute requirement is so vital that the California Highway Patrol incorporated it into its training manual for a DUI arrest and DUI investigations. In addition, breath sprays and mouthwashes may contain alcohol.  The use of such products can falsely inflate a breath result unless police wait an appropriate amount of time before administering a breath test.  By using an experienced DUI lawyer, you can mount a successful DUI defense and beat your DUI arrest!

A DUI defense should include an examination of any physical or health related issues that the driver had at the time of the DUI arrest.  Various physical conditions and health issues can also dramatically affect breath results by either restricting the volume of air that the lungs hold and thus changing breathing patterns, by causing mouth alcohol contamination or by changing body temperature.  Any significant lung disease, such as emphysema or asthma, can reduce the amount of air that a person can exhale, and change the breathing pattern by altering the length of time that a person is exhaling.   Millions of persons suffer from a medical condition, gastroesophageal Reflux Disease (“GERD”),that can cause the mouth to be contaminated with stomach gases, such as ethanol.     Any physical condition that alters body temperature can affect breath results.  For example, heavy exercise or fever can change body temperature, which impacts the breath results.

If a person submits to a breath test in the absorptive phase of his/her body’s processing of alcohol, there is a risk of a higher breath result.   Your DUI defense can be that the breath result is a false high read due to how the human body absorbs and then circulates the alcohol.   When the body first absorbs alcohol, the alcohol enters the arteries.  Because the arterial blood circulates to the lungs, breath results taken during absorption are higher and at times, much higher, than post absorption results.

The way a person breaths can also affect the breath results.  The longer a person exhales, the higher the result.  The alcohol content will continue to rise as the person exhales and not reach its peak level and establish a plateau effect until the end of the exhalation.    Some experts believe that this high read is cause by alcohol being initially deposited on the mucous in the air passages and subsequently exhaled.  By the end of the exhalation, the person is exhaling alcohol that has accumulated on the mucous in the passages as well.  Your DUI lawyer can review with you how the police had you blow into the various machines and what the effects of such breathing had on your test results!

Successful DUI defense can include attacking an assumption that is part of every breath result.  First, the machines are set to convert breath to blood readings at the same partition ratio for every person: 2100 to 1.   Many studies have shown that the partition ratio actually ranges quite widely among persons.

Another way to mount a successful DUI defense is to question if the machines are actually working.  All breath machines must be properly calibrated.  State law requires that each breath machine must be checked every 10 days or 150 uses, whichever comes first.   A technician not associated with law enforcement takes a known concentration of ethanol and shoots it through the machine.  The machine is designed to print out a tamperproof result, so that we can compare what we know the test sample to be to what the machine reads the test sample to be.  As part of the discovery process, your DUI attorney can request these machine accuracy and calibration logs. The logs will show what the alcohol content was that was used and then compare it to what the machine result THOUGHT the content was.  If the machine result is higher than the actual content, this can help you.  In addition, the calibration sample itself may have issues (ie improper preparation or aging of the test sample).

Lastly, each machine is designed to “purge” itself between uses by expelling the previous user’s alcohol through “air blanks.”  However, researchers believe that the machines are inefficient in purging themselves, thus leaving contaminants in their chambers from previous users that cause artificial high results.

Please contact DUI attorney Mark Blair immediately for a free, informative and confidential consultation.  See how Mark can help you prepare a successful DUI defense. You can reach Mark at (510) 845-4343.  Mark Blair practices daily in Oakland, Hayward, Fremont and Pleasanton courts in Alameda County.