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Is the breath test accurate in determining blood alcohol content? Law enforcement has used chemical breath tests in DUI investigations for years. The breath test itself is simple enough. Indeed, a person blows into a long-straw like item attached to an instrument. This subsequently produces an alcohol percentage read.
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Is the Breath Test Accurate in Measuring “Blood” Alcohol Content?
As scientific and conclusive as this sounds, a breath test does not actually measure “blood” alcohol content (BAC). Rather, it measures the alcohol content in the “breath”. Indeed, a mathematical formula converts the “breath” reading into an estimate of the person’s “blood” alcohol. Obviously, this estimate raises criticisms concerning the chemical breath test as conclusive proof of a person’s “blood alcohol level.”
Other Problems with Breath Test Accuracy
Chemical Compounds, Medications and other Drinks
Another problem is the breath test does not always distinguish between alcohol and other chemical compounds people have contact with. Undoubtedly, these compounds could impact a breath test result. Compounds such as acetone, isopropanol or methyl ethyl ketone. Moreover, medications such as albuterol, budesonide, and specific cold medications may impact a breath test result. Indeed, these are medications that either contain alcohol or remain in a person’s airways longer than other medications. In addition, drinks such as kombucha or other fermented beverages could impact the accuracy of the result.
Health Conditions and Breath Test Accuracy
Also, multiple other factors could impact breath test accuracy. These factors include age, gender, rate of consumption, and food and other beverage intake. Indeed, a computer does not easily simulate real-life factors such as these. Moreover, diabetes elevates acetone levels. Additionally, gastroesophageal reflux disease (GERD) could inflate breath test results. Specifically, a person regurgitates undigested alcohol impacting the test reading.
Deprivation Period
Law enforcement generally subjects a driver to a “deprivation period” prior to administering the breath test. This requires the officer to watch the suspect driver for at least 15 minutes to ensure no regurgitation or that there is nothing in the driver’s mouth. Time starts over if a person regurgitates. However, law enforcement many times will not appropriately conduct the “deprivation period.” Specifically, many officers conduct the “deprivation period” while driving to a DUI van or police department. An officer not watching a suspect driver is not appropriately conducting an observation of the “deprivation period.” These are important factors to identify and consider as it may significantly impact the breath result.
Periodic Maintenance and Calibration Records
In addition, A.R.S. 28-1323(A)(5) requires the prosecutor to establish the breath test device was in “proper operating condition” prior to admission of a breath result. The State establishes this through periodic maintenance and calibration records. It is important to have an attorney or expert review the records to ensure the breath test was properly functioning. Several factors may impact breath test instrument accuracy. As such, it is important to obtain and review these records.
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Huss Law as Your DUI Attorney
DUI breath test cases are not always as “air-tight” as one may think. Several factors exist and a breath test does not measure “blood” alcohol content. Indeed, chemical compounds, medications, and health conditions may impact the result. Moreover, a computer cannot simulate certain real-life factors and differences between humans. Jeremy L. Huss has been handling breath test DUI cases in Arizona for 20 years. He has trained law enforcement in conducting DUI investigations and spent years prosecuting them. If you are facing a DUI charge, Call Huss Law Today for a Free Consultation!