Blood Test for DUI

If you are arrested for DUI a blood test may be used to determine the amount of alcohol or drugs in your system.

There are three kinds of chemical tests used on DUI cases: blood tests, breath tests and urine tests. Blood tests can be the most accurate under ideal circumstances, and they can check for either alcohol or drugs. This is why they’re often preferred by law enforcement over breath tests, which screen for alcohol only.

In a blood test, a small sample of your blood will be drawn after your arrest. This sample will be sent to a lab for testing. The lab uses equipment that allows them to detect exactly how much alcohol is present in the blood sample, establishing your blood alcohol concentration (BAC).

It sounds scientific, but research has shown that there are many ways a blood test can go wrong. Potential errors include:

  • Drawing the sample incorrectly, which can contaminate it and lead to false positives.
  • Improper handling or storage of the sample. Your blood sample will contain yeast, sugar and bacteria, the three main ingredients of fermentation. If fermentation produces even a tiny amount of alcohol, it can dramatically change the test results.
  • Testing equipment may pick up some other substances as alcohol, reading your BAC as much higher than it really was.

With drugs, alcohol tests have similar handling and testing equipment errors. Additionally, habitual marijuana users may have THC in their system at all times, even if they are sober, and the use of a blood test is controversial.

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) 896-2724 and get your free consultation today.

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