Urine Test for DUI

Urine tests are used to screen for drugs or alcohol in a person who has been arrested for DUI. They are the least accurate chemical test.

If you’re arrested for DUI you will be asked to take either a breath test, blood test or urine test. Law enforcement usually prefers not to use a urine test because it is less accurate than the other types of chemical tests available. But there are circumstances where a urine test is the only choice.

Urine tests work indirectly. They can measure the presence of both alcohol and various drugs in the urine. But having a substance in your urine while driving is not illegal. Having it in your bloodstream is illegal. That means that a lab has to work backwards from the urine test result to estimate your blood alcohol concentration (BAC) or the amount of drugs in your system.

This process is riddled with errors:

  • Two people with the same BAC could give wildly different urine test results depending on how recently they urinated before the test, how long ago they drank, and how much non-alcohol liquid they drank.
  • Like blood tests, urine tests are subject to a variety of lab errors than can give false results.
  • Because of the problems with accuracy, a DUI suspect usually has to urinate once to empty the bladder, wait 20 minutes, and then give a urine sample. It isn’t always possible for a person to urinate this much.

Police will usually give you a urine test only if the other tests aren’t available, or if there is some clear reason you cannot take one of the other tests (such as asthma stopping you from taking the breath test). But you must take one of the three tests, and if only one is available, that is the one you must take. Otherwise you are charged with refusal.

Have you been charged with DUI? A good DUI lawyer can help fight your test results and potentially win your case. Let us 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) 862-0199 and get your free consultation today.

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