Are Marijuana DUIs Treated Like Alcohol DUIs in California?

Driving under the influence, whether of alcohol or marijuana, is a serious offense in California. Both are recreational substances that may be lawfully consumed in the state, but both alcohol and marijuana are subject to many laws and regulations, including the prohibition against driving while impaired by either substance. Yet marijuana DUIs aren’t handled in exactly the same way as alcohol DUIs. Understanding the differences is essential if you or someone you know is facing DUI charges involving cannabis.

Read on for a discussion of this important topic. If you have been arrested for DUI, DUI drugs (DUID), or the combined influence of alcohol and drugs in L.A., contact Kosnett Law Firm to review your options and mount a successful defense with the help of a skilled and experienced Los Angeles DUI defense attorney.

No Legal THC “Per Se” Limit

California law prohibits driving while impaired by any drug, including marijuana, under Vehicle Code § 23152(f). To secure a conviction, prosecutors must prove that the substance affected your nervous system or mental faculties sufficiently to impair your ability to drive as safely as a sober person would.

One of the key distinctions between alcohol and marijuana DUIs is the absence of a defined THC limit. For alcohol, California sets a clear “per se” blood alcohol concentration (BAC) threshold of 0.08%. Exceeding that limit leads to a DUI per se charge, even if you otherwise appeared capable of driving.

In contrast, California does not have a statutory THC threshold that automatically means impairment; there’s no equivalent “per se” limit when it comes to pot. Instead, marijuana DUIs are “effects-based.” They rely on evidence that impairment occurred, not simply that some amount of cannabis was detected.

Proving Impairment Is Tougher With Marijuana

Detecting THC in someone’s system doesn’t guarantee they are presently intoxicated. THC can remain in the bloodstream long after its effects have worn off, sometimes for days or weeks.

In fact, while BAC levels directly correlate with impairment, the same isn’t true for THC. As the Marijuana Policy Project (and the AAA foundation) have noted, there’s no THC concentration that reliably predicts impairment.

Chemical Testing: What’s Involved

For alcohol DUIs, breath and blood tests are standard and yield immediate, quantifiable results. With marijuana, no roadside breathalyzer exists. Instead, law enforcement must rely on blood tests (or occasionally urine or saliva), which only confirm the presence of THC, not impairment.

Blood tests for marijuana are slower and don’t indicate recent use, meaning prosecutors must rely on additional evidence, such as officer observations of behavior, physical signs (like bloodshot eyes), or how you were driving. In some cases, they may call a Drug Recognition Expert (DRE) for specialized impairment analysis.

Similar Penalties, Different Procedures

Despite these differences, penalties for first-time marijuana DUIs are often similar to those for alcohol DUIs. You could face fines (around $390), up to six months in jail, mandatory DUI school, probation, and a six-month license suspension.

However, a notable distinction lies in DMV action: when someone is arrested for an alcohol DUI with a BAC above 0.08%, the Department of Motor Vehicles will impose an instant administrative suspension pending a hearing. In marijuana cases, because the evidence isn’t immediately conclusive, these suspensions are usually held off until charges are formally resolved.

Why These Differences Matter

• Challenges for Prosecutors: Marijuana DUI cases are often harder to prove. Without a per se THC limit, prosecutors must build a more compelling case based on behavior, expert testimony, or DRE evaluations.

• Defense Opportunities: These challenges create openings for defense, for example, questioning the interpretation of test results, raising doubts about timing, or challenging procedural fairness.

• Public Awareness: Many drivers assume that a positive test alone is enough to convict and might not think about fighting the charges. It’s critical to emphasize that in marijuana DUI cases, that alone doesn’t automatically implicate impairment.

Contact Kosnett Law Firm for DUI and Drug Defense in Los Angeles

If you’ve been arrested for a marijuana DUI in California, know that the law treats these cases differently than it does alcohol DUIs. While penalties may be similar, the lack of objective thresholds for impairment means the outcome often comes down to how the evidence was collected and interpreted.

A skilled DUI defense attorney can scrutinize the stop, the testing procedures, and challenge whether the evidence truly establishes impairment. At Kosnett Law Firm, we understand both the science and the strategy behind marijuana DUI charges, and we’re here to defend your rights. Contact us today for a free case evaluation.