What Can Cause a False Positive Breathalyzer Test in Arizona?

With almost 30,000 DUIs occurring in Arizona each year, it is safe to assume that errors occur when determining if someone is under the influence. One such error that occurs far too often is a false positive result for a breathalyzer test.

How Do Police Officers Determine Drunk Driving?

An officer who pulls someone over under the suspicion of drunk driving will determine sobriety by performing two tests; a field sobriety test and a breathalyzer test. A field sobriety test is a group of three tests used to assess balance, coordination and the ability of a driver to divide his or her attention to more than one task during the field sobriety test.

The tests used in a field sobriety test are:

  • Balance: One leg stand
  • Coordination: Walk and turn
  • Divide Attention: Horizontal Gaze Nystagmus

Unlike the field sobriety test which requires movement, a breathalyzer test uses a mechanical device to assess the blood alcohol level of a driver. The breathalyzer test is the most important tool when determining whether or not someone is driving under the influence and the reading it gives will determine how harshly a driver will be charged.

Do You Have to Take a Breathalyzer Test in Arizona?

In Arizona, even though you have the right to refuse a breathalyzer test, you should not do so. If a driver refuses a breathalyzer test, they are not preventing themselves from being arrested for a DUI as an officer use other means to ultimately decide if they believe a driver is under the influence and arrest them. Instead, refusing a breathalyzer test only delays the process and it will result in will result in the following:

  • 1st Offense refusal to take the breathalyzer will result in a 1 year suspension of a driver’s license
  • 2nd Offense refusal to take the breathalyzer within 7 years of a previous one will result in a 2 year suspension of a driver’s license
  • 3rd Offense refusal to take the breathalyzer within 7 years of a previous one will also result in a 2 year suspension of a driver’s license

Breathalyzer Test Readings

An officer will perform a breathalyzer test to determine if a driver is over the legal limit of 0.08% blood alcohol level (BAC). If the BAC is above 0.08% the driver will be charged according Arizona’s three DUI categories:

  • Standard DUI is a BAC of 0.08-0.014, but for a commercial driver it is a BAC greater than 0.04
  • Extreme DUI is a BAC of 0.15-0.19
  • Super Extreme DUI is a BAC of 0.20 or greater

Breathalyzer tests are not reliably accurate and false positives occur often. If you have been charged with a DUI, there is a chance that the breathalyzer had an incorrect reading and an experienced DUI attorney can use this as a strong defense for your case.

What Causes a False Positive Breathalyzer Test

False positive breathalyzer test results are all too common, but many police officers and prosecutors do not recognize this as it may allow for a case to be dismissed. There are many reasons why false positives occur, here are the most common causes:

  • Improper Equipment Calibration
  • Medical Conditions such as acid reflux
  • Medications
  • Mouthwash
  • Contamination
  • Diet – For instance individuals on a low carb/keto diet will have increased levels of acetone in their breath which the device can register as alcohol
  • Timing of Test – If the test occurs less than 15 minutes after a drink was consumed the device will record the BAC as being much higher than it actually is
  • Vomit – If you vomit before taking a breathalyzer test there will be an increased amount of alcohol residue

One of the biggest contributors to false positive tests is acid in our bodies. Certain medications or medical conditions such as acid reflux disease cause the acid levels in the esophagus to increase and when a breathalyzer test occurs the build up of acid causes a phenomenon called “mouth alcohol”. The mouth alcohol effect will cause a breathalyzer test results to be much higher than they actually are.

Medical conditions such as GERD, acid reflux, heartburn or any medication that would cause an increase in acid in the body may create a false positive on a breathalyzer test. If you have been arrested for a DUI and have a medical condition or take medicine that increases acid levels in the body, contact us to schedule your free case review.

Call the JacksonWhite Criminal Law team at (480) 467-4370 to discuss your case today.

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