Can You Get a DUI for Marijuana or Drugs in California? Vehicle Code 23152(f) Explained
The short answer: yes. California charges driving under the influence of any drug, including legal marijuana and medication prescribed by your own doctor, under Vehicle Code section 23152, subdivision (f), and driving under the combined influence of alcohol and a drug under subdivision (g). Unlike an alcohol DUI, there is no legal limit for THC or any other drug; the prosecutor must prove that the drug actually impaired your driving. That makes drug DUI cases harder to prove and more defensible than most people realize, but it also makes the officer's observations and the drug recognition evaluation the center of the case. This guide explains what the District Attorney must prove, how these cases are investigated on the 10, 15, 60, and 215 freeways, the defenses that work, and the penalties.
What the Prosecutor Must Prove for a Drug DUI
The elements are simple to state and hard to prove. To convict under Vehicle Code section 23152, subdivision (f), the prosecution must prove beyond a reasonable doubt that (1) you drove a vehicle, and (2) when you drove, you were under the influence of a drug. A "drug" under Vehicle Code section 312 is any substance other than alcohol that could affect the nervous system, brain, or muscles so as to impair, to an appreciable degree, the ability to drive as an ordinarily prudent and cautious person would. That definition covers marijuana, methamphetamine, cocaine, opioids, benzodiazepines, sleep aids, and even some over-the-counter antihistamines.
"Under the influence" means impaired driving ability, not presence in the blood. The jury instruction for this charge tells jurors that a person is under the influence when, as a result of taking a drug, their mental or physical abilities are so impaired that they are no longer able to drive with the caution of a sober person using ordinary care under similar circumstances. The presence of a drug or its metabolite in your blood is evidence, but it is not enough by itself. The prosecution must connect the drug to actual impairment at the time of driving, and that connection is where most drug DUI cases are won or lost.
A prescription is not a defense. Vehicle Code section 23630 states that the fact that a person is entitled to use a drug under California law is not a defense to driving under the influence. The same rule applies to adult-use cannabis legalized by Health and Safety Code section 11362.1. A Hesperia driver with a valid prescription for hydrocodone or a Riverside driver who bought cannabis legally can still be convicted if the drug impaired their driving. The prescription matters for sentencing and negotiation, not for guilt.
Combined influence is charged separately. Vehicle Code section 23152, subdivision (g) covers driving under the combined influence of alcohol and a drug. Prosecutors in Riverside and San Bernardino counties use this count when a driver blows below 0.08 but the officer suspects marijuana or medication, and they commonly file it alongside the standard alcohol counts under subdivisions (a) and (b). Our guide to what happens after a DUI arrest in California explains how multiple counts are handled.
Why There Is No Legal Limit for Marijuana in California
California never adopted a per se THC limit. Some states treat a certain nanogram level of THC as automatic impairment. California has not, and the reason is scientific: blood THC levels do not track impairment the way blood alcohol does. A daily user can have measurable THC days after last use with no impairment, while an occasional user can be significantly impaired as THC drops. The inactive metabolite, carboxy-THC, can remain detectable for weeks and proves nothing about impairment at the time of driving.
That science is the defense's best friend. Because there is no per se limit, a drug DUI prosecution rests on three things: the driving pattern, the officer's observations and field sobriety tests, and the drug recognition evaluation. A blood result showing active THC helps the prosecutor, but a defense toxicologist can explain why the number does not establish impairment. Juries in Riverside, San Bernardino, and Los Angeles counties have acquitted in marijuana DUI cases where the driving was unremarkable and the "impairment" consisted of red eyes and the smell of cannabis.
Open container and smoking rules are separate violations. Vehicle Code section 23222 prohibits possessing an open container of cannabis while driving, and Vehicle Code section 23220 prohibits smoking or ingesting cannabis while driving. Those are infractions, not DUIs, but officers use an open container or the smell of fresh smoke as the reason to start a DUI investigation.
How Drug DUI Investigations Work in Southern California
It usually starts with a traffic stop for something else. A lane drift on the 15 through the Cajon Pass, a burned-out tail light on Bear Valley Road in Victorville, or a speeding stop on the 91 in Corona leads to the officer noticing dilated pupils, slow speech, or the odor of marijuana. Under Rodriguez v. United States (2015) 575 U.S. 348, the officer may not prolong the stop beyond the time needed for the traffic violation without reasonable suspicion of another crime, so the facts that justify extending the stop into a DUI investigation are the first thing a defense lawyer examines. Our guide to when police can search your car explains the related search issues.
Field sobriety tests were designed for alcohol. The standardized tests, including the walk-and-turn, one-leg stand, and horizontal gaze nystagmus, were validated for alcohol impairment at or above 0.08. They are far less reliable for cannabis and for prescription medications, and horizontal gaze nystagmus in particular is not expected with marijuana. Officers also use non-standardized tests such as the Romberg balance test and a lack-of-convergence eye test. Field sobriety tests are voluntary in California, and declining them politely is lawful.
The drug recognition expert evaluation is the prosecution's centerpiece. When an officer suspects drugs, agencies such as the California Highway Patrol, the Riverside County Sheriff, and the San Bernardino County Sheriff call a drug recognition expert, or DRE, to perform a twelve-step evaluation at the station. It includes pulse readings, pupil measurements in different lighting, muscle tone, injection site checks, divided attention tests, and an opinion about which drug category is involved. The protocol is detailed, and a DRE who skipped steps, took measurements out of order, or reached a conclusion the toxicology does not support can be cross-examined effectively.
Blood is the chemical test for drugs. Under Vehicle Code section 23612, a driver lawfully arrested for drug DUI is deemed to have consented to a blood test, and an officer who reasonably believes drugs are involved can request blood even after a breath test. Under Birchfield v. North Dakota (2016) 579 U.S. 438 and Missouri v. McNeely (2013) 569 U.S. 141, a blood draw without consent generally requires a warrant, and Inland Empire agencies routinely obtain electronic warrants in minutes. Our guide on refusing a breathalyzer or blood test explains the consequences of refusal under Vehicle Code section 13353.
Oral fluid swabs are showing up at the roadside. Some agencies use handheld oral fluid devices that screen for THC, methamphetamine, cocaine, opioids, and benzodiazepines. These are preliminary screening tools, not evidentiary tests, and their results are generally used to justify the arrest and the blood draw rather than to prove impairment. How much weight a court gives them depends on the device, the officer's training, and whether the blood confirms the result.
Defenses to a Marijuana or Drug DUI in California
No impairment at the time of driving. This is the core defense in most drug DUI cases. If the driving pattern is explainable, the field sobriety tests were performed reasonably, and the DRE's findings are inconsistent with the drug found in the blood, the prosecution cannot prove the second element. A defense toxicologist can explain tolerance, timing, and why a THC or medication level does not equal impairment. Our guide to what makes a criminal case weak covers how this evidence is evaluated.
Unlawful stop, prolonged detention, or unlawful arrest. If the officer had no lawful reason to stop you, extended the stop without reasonable suspicion in violation of Rodriguez v. United States, or arrested you without probable cause, the blood result and the DRE evaluation can be suppressed through a motion under Penal Code section 1538.5. Body camera footage is essential here, and it should be requested immediately through discovery under Penal Code section 1054.1.
Problems with the blood draw and the lab. Blood must be drawn by qualified personnel in a medically reasonable manner under Schmerber v. California (1966) 384 U.S. 757, and the sample must be properly preserved, stored, and tracked through a documented chain of custody. Laboratory quantitation for THC and many medications has known margins of error, and a result that reports only an inactive metabolite does not show impairment. A defense lawyer should obtain the lab's full case file, not just the one-page result.
The DRE protocol was not followed. The twelve-step evaluation has to be done in order and completely, and the opinion has to match the toxicology. A DRE who called "cannabis" when the blood showed only a benzodiazepine, or who did not measure pupils in all three lighting conditions, has given the defense a powerful cross-examination. Many Inland Empire DUI arrests happen without any DRE at all, leaving the prosecution with a patrol officer's general impressions and a blood number.
Statements and Miranda. Admissions such as "I smoked a joint an hour ago" are often the strongest evidence of impairment, and they are usually made during roadside questioning before any warning under Miranda v. Arizona (1966) 384 U.S. 436. Roadside questions during a traffic stop usually do not require Miranda warnings, but custodial questioning at the station does. The practical lesson is covered in our guide to what not to say to police: identify yourself, provide your documents, and decline to discuss what you consumed.
Penalties for a Drug DUI in California
A first-offense drug DUI is a misdemeanor. The punishment range for Vehicle Code section 23152, subdivision (f) is the same as for an alcohol DUI: a misdemeanor with possible county jail time, fines and penalty assessments, a DUI education program, and probation for three to five years under Vehicle Code section 23600. Prior DUI convictions within ten years increase the mandatory minimums, and a fourth DUI within ten years or a DUI with a prior felony DUI is a felony. A drug DUI that causes injury is charged under Vehicle Code section 23153, as explained in our felony DUI guide.
The license consequences are different from an alcohol DUI. The DMV's administrative per se suspension under Vehicle Code section 13353.2 is triggered by a blood alcohol level of 0.08 or more, so a pure drug DUI with no alcohol does not produce an immediate administrative suspension. The suspension instead comes from the DMV upon conviction under Vehicle Code section 13352. If you refused the blood test, however, Vehicle Code section 13353 imposes a refusal suspension and you must request a hearing within ten days, as explained in our guide to the DMV hearing after a DUI.
Negotiated outcomes are common when impairment is doubtful. Because drug DUI cases are harder to prove, prosecutors in Riverside County, San Bernardino County, and Los Angeles County more often agree to a wet reckless under Vehicle Code section 23103.5, a dry reckless under Vehicle Code section 23103, or a dismissal when the DRE is missing or the blood shows only a metabolite. Those offers usually come at the pretrial conference after the defense has obtained the body camera footage and the full lab file. Our guide to plea deals in California explains how to evaluate them.
Collateral consequences reach beyond the courtroom. A DUI conviction appears on a background check and on your driving record for ten years for priorability purposes. Commercial drivers face separate consequences for their commercial license. Nurses, teachers, and other licensed professionals must often report the conviction. For non-citizens, a simple DUI is generally not a deportable offense under Leocal v. Ashcroft (2004) 543 U.S. 1, but a drug-related conviction can raise controlled substance questions that an alcohol DUI does not, so counsel must advise carefully under Padilla v. Kentucky (2010) 559 U.S. 356.
Where Drug DUI Cases Are Heard in Southern California
Each county has its own courthouses and practices. Riverside County drug DUI cases are heard at the Riverside Hall of Justice, the Southwest Justice Center in Murrieta for Temecula and Murrieta arrests, the Larson Justice Center in Indio for the Coachella Valley, and the Banning Justice Center. San Bernardino County cases go to the San Bernardino Justice Center, the Rancho Cucamonga courthouse, the Fontana courthouse, or the Victorville courthouse for High Desert arrests in Victorville, Hesperia, Apple Valley, and Adelanto. Los Angeles County cases are spread among the Clara Shortridge Foltz Criminal Justice Center, Van Nuys, Pomona, Long Beach, and Torrance, and Orange County cases go to the Central Justice Center in Santa Ana, the Harbor Justice Center, the North Justice Center, or the West Justice Center. Confirm the courthouse and your date on the superior court's website.
High Desert cases have their own patterns. Drivers on the 15 through Hesperia and Victorville, on Highway 18 through Apple Valley, and on the 40 toward Barstow are frequently stopped by the California Highway Patrol, and DRE availability varies in the High Desert. A missing DRE evaluation is a recurring theme in cases we see from the Victorville courthouse and the Barstow courthouse, and it changes the negotiation. Daniel Gramling, Esq. defends DUI cases in all of these courthouses and explains the strategy on our DUI defense page.
Frequently Asked Questions
Is there a legal THC limit for driving in California?
No. California has no per se THC limit, so a drug DUI under Vehicle Code section 23152, subdivision (f) requires proof that marijuana actually impaired your ability to drive with the caution of a sober person. A blood result is evidence of use, not proof of impairment, and daily users can test positive for active THC long after any effect has worn off.
Can I get a DUI for taking my prescription medication?
Yes. Vehicle Code section 23630 says that being legally entitled to use a drug is not a defense. If a prescription opioid, sleep aid, muscle relaxant, or anxiety medication impaired your driving, you can be convicted. The prescription and your doctor's dosing instructions still matter for the defense, because a person taking medication as directed over a long period often develops tolerance that undercuts the claim of impairment.
Do I have to take a blood test if the officer suspects drugs?
After a lawful arrest, refusing has serious consequences. Under Vehicle Code section 23612 you are deemed to have consented to a blood test when lawfully arrested for drug DUI, and refusal brings a suspension under Vehicle Code section 13353 plus sentencing enhancements. Officers can also obtain a warrant for your blood. Field sobriety tests and the roadside oral swab, by contrast, are voluntary before arrest.
Will I lose my license for a marijuana DUI?
Not immediately, unless you refused or had alcohol in your system. The DMV's administrative suspension under Vehicle Code section 13353.2 is based on blood alcohol, so a drug-only arrest does not trigger it. A suspension follows a conviction under Vehicle Code section 13352. Beating the criminal case or negotiating a reckless driving plea therefore protects your license in a way that is not possible in a high-BAC alcohol case.
Is a drug DUI easier to beat than an alcohol DUI?
Often, yes. There is no per se limit, field sobriety tests were validated for alcohol, drug recognition evaluations are frequently incomplete or missing, and blood results for THC and many medications do not establish impairment. That does not mean the case will be dismissed automatically; it means the defense has more to work with. Our guide on whether you need a lawyer for a first DUI explains why professional representation matters, and flat-fee DUI defense makes the cost predictable.
Can a drug DUI be charged as a felony?
Yes, in the same situations as an alcohol DUI. A drug DUI that injures another person is charged under Vehicle Code section 23153, and a fourth DUI within ten years or a DUI with a prior felony DUI conviction is a felony. A felony DUI goes through a preliminary hearing and carries possible state prison time, so early defense work is critical.
Gramling Law Group defends marijuana and drug DUI cases at the Riverside Hall of Justice, the Southwest Justice Center, the Larson Justice Center, the San Bernardino Justice Center, the Rancho Cucamonga courthouse, the Victorville courthouse, the Barstow courthouse, and courthouses throughout the Inland Empire, Los Angeles County, Orange County, and Southern California. Daniel Gramling, Esq. offers flat-fee criminal defense and limited-scope options so you know the cost before the case begins. Call (909) 654-4575 or contact us through this website for a consultation.
This article is educational and is not legal advice. Reading it does not create an attorney-client relationship. It addresses California law only.
Related Guides From Gramling Law Group
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