DWI: Challenging the Breath Test

The state of Minnesota and the State of Wisconsin currently require a person suspected of a DUI/DUI to submit to a blood, breath or urine test to determine the blood alcohol content of the subject. A refusal to submit to such a test may have more serious ramifications than a test result with a BAC over the legal limit.



The Intoxilyzer 5000 is the current breath-testing machine that is used. This is the machine that is used when a DWI/DUI suspect is taken to the police station and should not be confused with the preliminary breath test (PBT) that may be used at the scene of a DWI/DUI stop. The PBT is not admissible as evidence in Court whereas, the results of the Intoxilyzer 5000 may be critical to a prosecutor's case.



The manufacturer of the "Intoxilyzer" is CMI, a Kentucky corporation. Though the Intoxilyzer has the potential to be accurate, it is not infallible. Breath testing in general is based upon the principle that there is a direct relationship between the amount of alcohol in a person's deep lung air to amount of alcohol in the person's blood in the aveolar tissue of the lungs. Breath testing equipment is calibrated based upon the assumption that the ratio of alcohol in the air to the alcohol in the blood is 1 to 2100.



THIS RATIO IS INACCURATE BASED ON INDIVIDUAL DIFFERENCES.



Research has clearly demonstrated that the ratio between breath and blood may vary between individuals. This is critical since a person with a ratio lower than 2100 to 1 will result in an inaccurate and high blood alcohol test result from a breath sample.



BREATHING TECHNIQUES MAY AFFECT TEST RESULT



Breathing techniques may also affect the Intoxilyzer 5000 reading. A longer breath sample - over ten seconds - may result in a higher BAC reading by more than 100% since the machinery is calibrated to test a 10 second sample. Additionally, a person who breaths shallow or holds their breath may accumulate residual mouth alcohol resulting in a higher reading than their true BAC. Hyperventilation may also impair the test. The affect of breathing techniques on Intoxilyzer results was confirmed in recent research conducted at the University of Washington Department of Medicine by by Dr. Michael Hlastala.



OUTSIDE RADIO SIGNALS MAY AFFECT DEVICE



Numerous reports and scientific articles have demonstrated that the Intoxilyzer 5000 becomes unstable if it is in proximity to any other devices emitting radio waves. A police officer's radio or proximity of the machinery to the airport may cast doubt on the accuracy of test results.



MOUTH ALCOHOL AND CONTAMINATION FROM OTHER SOURCES



Today's breath testing equipment relies on and infrared analysis of the breath sample to determine how much alcohol is present in a breath sample. A major flaw in the the instrument is its inability to differentiate between alcohol in a subject's mouth and alcohol from the lungs (the deep lung air).. analysis is that many of these instruments are non-specific for alcohol. Residual mouth alcohol can be created by having foreign objects in the subjects mouth which retain alcohol, such as denture adhesives, chewing tobacco, gum and others.



MACHINES MAY DETECT OTHER CHEMICALS AS ALCOHOL



The Intoxilyzer machine has great difficulty detecting molecules which have a similar structure to ethyl alcohol. There are many molecules in the methyl group which includes ethyl alcohol. The Intoxilyzer bombards a breath sample with infrared light. The light absorption is then tested based upon the Baer-Lambert theory stating that organic substances absorb infrared energy at different wave lengths. The wave lengths tested by the Intoxilyzer 5000 are 3.39 and 3.48 microns. However, there are a number of other similar substances that also absorb infrared light at these wave lengths. Chemicals that are commonly used in wood working or construction may be inhaled, or even a strong presence of chemicals on a person's clothing may be read by an Intoxilyzer as alcohol.



PHYSICAL DISABILITY MAY AFFECT READING



Certain illnesses or disabilities may also create chemical reactions in the body which affect an Intoxilyzer reading. A person with heartburn, liver disease or diabetes may have chemical reactions in the body that the impairs a breath sample. . The same can be said of people with certain diets, or those on certain medications. Hyperventilation or sitting in certain positions may also cause sample error on a breath test. Further, the subject's exposure to certain chemicals such as acetone may result in an inaccurate breath alcohol test result.



BREATH TEMPERATURE MAY AFFECT READING



the temperature a person's breath may have a critical impact on the accuracy of a breath test. The Intoxilyzer 5000 is calibrated to test breath at 34 C. This is the same temperature that is used for simulator solutions. However, breath samples provided may not always register at exactly 34 C. Even a slight difference may have a critical impact. may not always. A variation of only one degree may result in a BAC reading that is 7% higher.



HOW ARE RESULTS CHALLENGED



Intoxilyzer results are challenged by reviewing intoxilyzer maintenance records, police reports and subject test results. Often, these documents will clues will provide clues to inaccurate testing. Erroneous tests may be suppressed so that they cannot be used at trial and if suppressed, may render the prosecutor's case weak and impossible to win.





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Maury D. Beaulier is recognized as a leader in Minnesota DWI law and criminal defense. He has represented clients successfuly across the state with agressive strategies. Mr. Beaulier can be reached on his website at http://www.dwicounsel.com