How Reliable are Breath Tests?

How Reliable are Breath Tests?

If law enforcement suspects that you may be driving above the legal limit of .08% BAC, they may pull you over and ask you to submit a breath test to confirm these suspicions. Drunk driving convictions often rely on breath or blood test results, so refuting the validity of the tests is a valuable defense strategy for those charged with an OWI. 

Failing a breath test does not guarantee an OWI conviction. Breath tests are far from foolproof, and an OWI/DUI defense attorney will conduct a thorough investigation on your behalf to assess whether or not the test was correctly administered. If your attorney can prove it wasn’t, your charges may be reduced or dismissed.

Breath Tests Are Not Foolproof

Many different factors may impact the reliability of the breathalyzer test results. An experienced criminal defense attorney may investigate the following questions to build a defense for your case:

  • Was the breathalyzer test adequately calibrated? A technician must adjust breathalyzer software to ensure that BAC is accurately measured. 
  • Was the mouthpiece changed between sample breaths?
  • How hard did the officer ask you to blow into the device? Blowing too hard or too softly can impact the results.
  • Was the test given immediately at the traffic stop or was there a delay? Breathalyzer tests reflect your BAC when they are administered, but they do not necessarily reflect your BAC when you are operating the vehicle. If testing was delayed for any reason, this could discredit the validity of the test. 
  • Are the results borderline .08 BAC? If the breath test indicates that you are at or near the legal limit, a slight delay in breath test administration may mean that your BAC was not above .08 when you were behind the wheel. 

If you were given a breath test during a traffic stop or at a police station, the answers to the above questions might be the difference between a dismissal and a conviction. 

What Should I Do If Pulled Over For Suspected Drunk Driving?

Say as little as possible when pulled over. Law enforcement may ask you directly if you have been drinking. If they do, remember that the 5th Amendment of the US Constitution protects you from self-incrimination. The less you share, the better. Refusing to take a breathalyzer test can result in license suspension, so it is in your best interest to take the test if prompted to do so by law enforcement. Fortunately, your attorney may be able to demonstrate errors in test administration to prosecution, which could invalidate the evidence. If pulled over for suspected intoxicated driving, contact an experienced DUI/OWI defense attorney as soon as possible to ensure your rights are honored.