Even though recreational use of marijuana is now legal in California, it is still unlawful to drive its influence. (Vehicle Code §23152(f).) While the “per se” law makes a driver presumptively “under the influence” of alcohol at 0.08% BAC, how does the law define a driver under the influence of marijuana? The legal standard is that the driver’s ability to drive, with the same caution of a person who is not high under the same circumstances, is appreciably affected or impaired by the influence of marijuana. But there are two problems with this standard as far as it concerns driving under the influence of marijuana:

  • The Legislature has set no legal “per se” threshold by which a driver is presumptively under the influence of marijuana to the extent that the driver’s ability to drive safely is compromised and
  • There is no reliable test that can determine how much marijuana has been consumed by a driver or even when the consumption took place.

As to the first issue, even science has not settled on how or how much marijuana may affect a driver’s ability to drive safely. Studies, up to this point, are all over the place with some studies even suggesting that someone high on marijuana is a more cautious driver than someone who is stone cold sober. Indeed, the National Highway Traffic Safety Administration (NHTSA) recently issued a report: Marijuana-Impaired Driving|A Report to Congress (July 2017) wherein that agency reviewed the research and noted the wide variability in results, also noting research that suggests drivers under the influence of marijuana tend to drive slower, give greater distance between cars, and take fewer risks that drivers who are sober.

Tests for marijuana in a person’s system are not reliable. THC, the active ingredient in marijuana can linger in a person’s system long after the effects have worn off. Tests have found that THC, for some individuals, still shows in the blood 30 days after the last ingestion of the substance. Other studies have shown that people who do not use marijuana frequently can ingest (smoke) marijuana and have no evidence of the substance in their blood at the time they are actually high. Additionally, tests for THC don’t show what is going on in the person’s brain.

Scientists are working on other detection tests, such as breath and saliva tests but as it is now, a cop must rely on his or her subjective evaluation of a driver to determine if the driver is high on pot to the extent that the driver is a danger on the road. In Colorado, where marijuana has been legal for several years, some police officers are going through real life training. Volunteers get high and the police then practice sobriety tests on the volunteers. Problem is, the volunteers all perform differently even though they all smoked a lot of pot before subjecting themselves to the officer’s tests. Some of the volunteers failed the tests but some did just fine.

It’s not hard to see the problems here. Unlike driving under the influence of alcohol where tests are reliable, as are tests for other drugs that are easily measured in the blood and dissipate as the effects wear off, establishing whether a driver is unlawfully under the influence of marijuana is left almost entirely to the subjective decision of the officer. But on the flip side, this may offer a strong defense to those charged with driving under the influence of marijuana.

Whether you or a loved one has been charged with driving under the influence of alcohol or drugs, including marijuana, a skilled defense attorney can make a significant difference in the outcome. William Weinberg has been defending DUIs and DUIDs for almost 25 years. Contact Mr. Weinberg at his Irvine office at (949) 474-8008 or by email at bill@williamweinberg.com

Posted in:

Comments are closed.