10 Instances Where Breathalyzer Tests Can Be Inaccurate

Quantifying the impact of alcohol upon a person has long been a goal of the scientific community, with studies dating back as early as 1874. In the contemporary legal setting, the breathalyzer test, also known as alcohol breath testing, is touted as a highly accurate and definitive tool for detecting Blood Alcohol Content (BAC). BAC is a vital measure for determining if someone is operating a vehicle under the influence of alcohol. Unfortunately, breathalyzer tests are not always as accurate as they are portrayed to be. Here are 10 instances where breathalyzer tests can miss the mark:

  1. Breath machines are responsive to temperature and will provide inaccurate readings if not calibrated to adjust to a change in ambient temperature.
  2. The pattern of breathing may affect the validity of a test. Holding your breath for 30 seconds could result in an increase of a BAC of .07% to .081% or more.
  3. Research has shown breath alcohol tests are higher than blood alcohol tests by approximately 15%.
  4. If a breath test taker is on a diet or if they are a diabetic or undiagnosed diabetic, The National Highway Traffic Safety Administration has found these people are at risk of elevated acetone levels, with some people experiencing acetone levels hundreds or even thousands of times higher than in the average person. Acetone tests as ethanol in a breath test machine.
  5. Many everyday substances that are common in some professions are capable of triggering a false positive breathalyzer result for test takers. Examples include paint, lacquer, cleaning solvents, ethers, and non-drinking alcohols.
  6. Alcohol lingering within an individual’s mouth can contaminate an otherwise valid breathalyzer test. Mouth alcohol is presumed to be gone from the mouth after 15 minutes, and California law requires that an officer observes an individual for 15 minutes before performing a breathalyzer test to ensure the results are not contaminated.
  7. Certain bread products have also been reported to trigger false positive tests on breathalyzer machines due to various ingredients skewing the results of the test.
  8. Acid reflux is caused when stomach material comes into the mouth because of a defective or herniated valve between the stomach and the trachea. This common health reaction is capable of creating an invalid test by leaving alcohol residue within your mouth, compromising the breathalyzer result.
  9. Some breathalyzer tests are susceptible to Radio Frequency Interference. Significant radio traffic coming from the police cruiser could potentially impact test validity by disrupting the radio frequency used by the testing machine.
  10. Long-term smokers have an inherently higher breath alcohol content because of the presence of acetaldehyde, potentially skewing their breathalyzer results.

Arizona has three levels of DUI.

DUI – An individual can be found guilty of a DUI offense if they are operating a vehicle with a blood alcohol content between .08 and .14. This is the most basic drunk driving offense in Arizona.

Extreme DUI – An individual can be found guilty of an Extreme DUI If they operating a motor vehicle with a blood alcohol content of .15 or more.

Aggravated DUI – An individua can be found guilty of an aggravated DUI offense if they are operating a motor vehicle and have a blood alcohol content of .08 paired with one of the following circumstances:

  • Driving on a suspended or revoked license;
  • Having committed two prior DUIs in the past seven years;
  • Driving with a passenger under the age of 15 years old; or
  • Refusing to submit to a breath sample (for those ordered to have an ignition interlock on their vehicle).

Have You Been Arrested for an Arizona DUI?

If arrested for DUI, you have the right to an attorney to defend you against your charges. If you are facing criminal charges for DUI in Arizona, call us at The Law Office of James E. Novak. We are committed to advocating for your rights and exploring every aspect of your case to find the holes in the prosecution’s charges against you. For a free and confidential consultation, call us at 480-413-1499.

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