California has commissioned the Center for Medicinal Cannabis Research at UC San Diego to develop a reliable detection method

In 2016, two decades after the approval of Proposition 215, California voters approved Proposition 64, the Control, Regulate and Tax Adult Use of Marijuana Act (AUMA). As of January 1st, 2018, it is now legal in the state of California for an adult to smoke Marijuana. They may do so without fear of punishment or fines from State authorities. Marijuana remains illegal under Federal law, however, creating some legal uncertainty for California residents and businesses wishing to participate in the new economy that is estimated to generate up to $1B in new tax revenue.

As it turns out, there is still no clear legal standard that defines when a person is too high to get behind the wheel. Where the California vehicle code established a Blood Alcohol Content (BAC) of 0.08 percent as the threshold for a regular DUI for anyone 21 or older, no such standard exists for the Marijuana DUI. In part, this is because officers don’t have the proper analysis tools and haven’t been trained properly on how to use them.

Tetrahydrocannabinol, or THC, is the active drug in marijuana but it is exceedingly difficult to detect. As of this writing, there are no widely accepted sobriety tests for determining whether a driver is too high to drive. CHP officers use field tests, which we’ve shown numerous times in court to be too subjective. San Diego Police officers use a Swab test for their DUI checkpoints where they take a saliva sample from the driver. This technique has not resolved the issue either since it has resulted in some false or misleading readings.

California Assembly Bill 266, “The Medical Marijuana Regulation and Safety Act,” passed the legislature last year. Among its provisions, it allowed the State to commission the Center for Medicinal Cannabis Research at the University of San Diego to help with the detection of driving under the influence of Cannabis.

With the help of a $1.8 million grant from the State, the clinical study will ask volunteers who meet their criteria to inhale smoked cannabis at the beginning of the day and then complete driving simulations, iPad-based performance assessments, and bodily fluid draws (e.g., blood, saliva, breath) before the cannabis smoking and hourly over the subsequent 7 hours after cannabis smoking. A smaller group will smoke a placebo. The study should determine how much you need to smoke to affect driving performance, how many hours the impairment lasts, if saliva or “expired” air is a reliable substitute for blood sampling, and if officers can use an iPad to administer a newly formulated standard field sobriety test. The lead investigators are Thomas Marcotte, Ph.D. and Barth Wilsey, M.D. According to the web site, the clinical study is still active.

While I recognize Californians need a clear legal standard for determining whether an adult is too high to drive, I’m skeptical whether it’s even possible to achieve the objectives laid out in this clinical study. I will certainly keep an open mind, but short of an actual blood sample, it will probably be almost impossible to determine a universal threshold for a marijuana DUI and whether it can be determined from a driver’s breath or saliva. Individual tolerance, metabolism, fatigue level, and other factors make it a difficult challenge to develop a legal standard.

About Joshua Price

Were you pulled over for DUI in San Diego? Did you consent to having a field sobriety test performed? I am experienced in dealing with cases involving failed or refused field sobriety tests. As an accomplished DUI attorney with over two decades of legal experience, I am highly skilled in defending DUI cases throughout San Diego and the surrounding areas in Southern California. Even if you performed poorly on field sobriety tests or failed a breath or blood test, I can accurately assess the situation and determine how to represent your interests for a favorable outcome.

Further Reading

Center for Medicinal Cannabis Research

Full Text of Assembly Bill 266 (AB 266)

Full Text of Proposition 64 (AB 64)

A New Front on the War on Drugs?

San Diego Police Will Target Marijuana DUI’s with a new Swab Test

Can I Get Busted for a DUI Because of Marijuana

California Driver Handbook – Alcohol and Drugs