Mouth Alcohol

Mouth alcohol” refers to traces of alcohol from mouthwash, medicine, burping, or other sources that throw off a DUI breath test. 

In a DUI case, the results of a breath test are often seen as conclusive. If the test says you were drunk, you must have been drunk, right? But the reality isn’t always so clear cut. A number of factors can throw off a breath test, causing someone with only a small amount of alcohol in their system—or none at all—to appear inebriated. One common cause of this is mouth alcohol.

Mouth alcohol refers to any trace amounts of alcohol in your mouth that wrong register as blood alcohol on a breath test. Mouth alcohol can and does send innocent people to jail for DUI, which is why it’s so important to get the advice of an experienced lawyer hen you face a DUI charge. Understanding how the breath test works is key to defending yourself.

Blood Alcohol vs. Mouth Alcohol

A DUI breath test is supposed to measure your blood alcohol concentration (BAC), the amount of alcohol in your bloodstream. To do this, it needs to get a sample of air from deep in your lungs. This air contains a tiny amount of alcohol vapor that is released by the blood as it passes through the lungs to get oxygen. In theory, testing the alcohol vapor in this air gives an accurate reflection of BAC.

But it doesn’t always work that way. To take a breath test, you have to blow a long, deep breath into the testing device. Although the air may start in your lungs, it passes through your throat and mouth on the way out. Any alcohol in the throat or mouth can contaminate it, and is read as a higher BAC by the testing device. This is “mouth alcohol.”

What causes mouth alcohol?

There are many possible sources for mouth alcohol. The most common include:

  • If there is alcohol in your stomach and you burp (or vomit), it can cause mouth alcohol. Having alcohol in your stomach isn’t necessarily illegal because it may not have been absorbed into the blood yet, and may not have affected your driving.
  • Many mouthwashes and breath sprays are alcohol-based. If you used one shortly before being arrested, you may have mouth alcohol.
  • Some medicines contain alcohol, especially cough syrups and natural herbal tinctures. These can also cause mouth alcohol.

What if mouth alcohol is a factor in my DUI case?

Police are supposed to prevent mouth alcohol from affecting your case by carrying out an “observation period” before testing you. This is a 15 minute period where an officer watches to make sure you don’t burp, vomit, or eat or drink anything. But police don’t always carry out the observation period, and 15 minutes may not be enough time to get rid of mouth alcohol in all cases.

The best way to find out if mouth alcohol could be a factor in your case is to speak to a DUI lawyer. Your lawyer can advise you of the best defense for your case. In many cases they can get faulty evidence, like breath tests, thrown out of your case altogether.

Let us help. We can connect you with an experienced Los Angeles DUI lawyer and get you a FREE consultation. Fill out the form to the right or call (310) 896-2724 and get your free consultation today.

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