Posted by Phillip Crawford | May 15, 2020

What about if I used drugs (marijuana) but didn't drink alcohol, can I still be charged with a DUI?

Yes, but it will be difficult for the district attorney to prove the case against you if you have a skilled DUI lawyer on your side.

In California, DUI charges are not exclusive to alcohol use. You can be charged with a DUI if the police believe you were driving under the influence of alcohol, any drug (including legally prescribed drugs) (Vehicle Code Section 23152(f)), or a combination of drugs and alcohol (Vehicle Code Section 23152(g)). The consequences of being convicted of a drug DUI in court are similar to being convicted of an alcohol DUI. However, DUI cases involving drugs (or a combination of drugs/alcohol) are very different from DUI cases involving only alcohol. These cases tend to have different defenses from alcohol DUI cases.

In California, there is no “legal limit” when it comes to drugs. For alcohol, it is illegal to operate a motor vehicle with more than .08% Blood Alcohol Content (BAC). However, there is no such limit established for any other drug. For example, there is no amount of THC (Delta-9-tetrahydrocannabinol) that is “illegal” to have in your system while driving in California.

There are many good reasons why California has not established a “legal limit” for drugs like marijuana, methamphetamine, ecstasy, heroin, etc. Most importantly, there is no good scientific evidence that simply having a certain amount of these drugs in your system makes you unsafe to drive. Alcohol is fairly unique amongst drugs in that it does not stick around in a person's system long after the effects have worn off. Almost all other drugs can remain in a person's system long after the effects of the drugs have subsided.

This concept has been acknowledged by the National Highway Traffic Safety Administration (NHTSA), which is the federal agency that oversees highway safety. In a 2017 report to Congress, NHTSA stated:

 “THC level in blood (or oral fluid) does not appear to be an accurate and reliable predictor of impairment from THC.”

Despite the fact that NHTSA acknowledges that there is no “unsafe” THC level in a person's blood, prosecutors in California continue to rely on blood tests to try to prove that a person is impaired by marijuana. In addition to blood tests, prosecutors will rely on the following evidence to prove that you were “under the influence” of drugs:

  • Any unusual or unsafe driving (swerving, speeding, failing to stop, etc.);
  • The police officer's observations about your appearance (odor of drugs, slurred speech, red/watery eyes, dilated pupils, unsteady gait, etc.)
  • Your performance on Field Sobriety Tests (FST's) (NOTE: you do not have to do these tests);
  • The results of a “Drug Recognition Evaluation” (DRE) (NOTE: you also do not have to do this); and
  • ANYTHING you say to the police. (NOTE: read here about why people should not speak with cops)

In drug DUI cases, prosecutors primarily rely on “Drug Recognition Evaluation” (DRE) results. A DRE is essentially a longer series of Field Sobriety Tests, which includes taking measurements of vital signs and an examination of the eyes. DRE tests are not scientifically validated, are generally unreliable, and often are performed incorrectly. A skilled DUI lawyer can show how these tests are flawed.

If you are arrested for a drug DUI in California, you are required to give a blood sample. (If you refuse to give a blood sample, you can lose your driver's license for at least one year, even if you are found not guilty of DUI.) However, you are not required to participate in the DRE tests (or any Field Sobriety Tests). If you have been arrested for a DUI and the police ask you to undergo a DRE, you can politely refuse to do so. 

Just because you had drugs in your system when you were driving does not mean that your case is hopeless. If you have been charged with a drug DUI, a skilled DUI lawyer can review the evidence collected by the police and can advocate on your behalf. We have successfully defended many drug DUI cases and take pride in our successful results.

Don't give up without a fight. Give us a call today for a free consultation.

About the Author

Phillip Crawford

Phillip Crawford is an award-winning DUI attorney. In 2018, he won the California DUI Lawyer's Association's top honor when he received the President's Award for excellence in DUI defense. His sole focus is defending DUI cases. Phillip is regarded by judges, prosecutors and fellow defense attorneys as the top DUI in the area who fights passionately for his clients.

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The Crawford Law Firm has been committed to its clients for over fourteen years. With offices in Monterey, Santa Cruz, and Salinas, CA, our focus is DUI and criminal cases in Monterey, Santa Cruz, San Luis Obispo, and Santa Barbara counties.

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