Experienced Nashville Defense Firm

Can a Breathalyzer Give a False Positive?

If you get stopped on suspicion of driving under the influence of alcohol, you will likely be given a breathalyzer test by the officer. This is one test that Tennessee law allows to help the officer determine if you are under the influence of alcohol. It is done through a machine that measures your blood alcohol content.

According to BacTrack, a breathalyzer is not the most effective method of measuring BAC. An actual blood test is, but this is not something that can be done roadside in the moment when an officer needs the information, so breathalyzer tests have become common. 

It is widely held that the results of a breathalyzer can be incorrect, which is why they are not used in court as evidence. The results could be impacted by various things. If you smoke a cigarette before the test, for example, it could affect the results. Similarly, breath mints, hairspray, fumes from paint and other similar things can also affect the results.

False positives may also occur if you have diabetes or are on a certain type of diet. This occurs because the testing devices can be affected by the ketones in your breath, which could be high due to your diabetes or your diet instead of being high because you were drinking alcohol.

Other things that could lead to a false positive result include an improperly calibrated machine, software issues, and human error. This information is intended to educate. It is not to be taken as legal advice.