Driving Under the Influence of Drugs Charges (Vehicle Code § 23152(f)) in California

Arrested for Drug DUI in California?

Driving under the influence isn’t just about alcohol. In California, it’s also a crime to drive while under the influence of any drug—including prescription medications and over-the-counter drugs—if that substance impairs your ability to drive safely. Under Vehicle Code § 23152(f), driving under the influence of drugs can result in jail time, license suspension, hefty fines, and a permanent mark on your criminal record.

At David P. Shapiro Criminal Defense Attorneys, we help people across San Diego fight back against drug DUI charges. Whether you were pulled over for weaving, failed a field sobriety test, or tested positive for a substance in your bloodstream, you still have rights—and we’re here to protect them.

What is Vehicle Code § 23152(f)?

Vehicle Code § 23152(f) states:

“It is unlawful for a person who is under the influence of any drug to drive a vehicle.”

This law applies to any substance that affects your nervous system, muscles, or brain in a way that impairs your ability to operate a vehicle like a sober, cautious person would under similar circumstances.

What Counts as a “Drug”?

The law does not distinguish between legal and illegal drugs. It includes:

• Illegal drugs like heroin, meth, or cocaine
• Prescription drugs like Xanax, Oxycodone, or Ambien
• Medical or recreational marijuana
• Over-the-counter medications like antihistamines, cold medicine, or sleep aids

Even if you were using a substance legally or with a valid prescription, it is still a crime to drive while impaired by it.

How Are DUID Charges Investigated?

Unlike alcohol DUIs, which use a blood alcohol content (BAC) limit of 0.08%, there is no set threshold for drugs. That means DUID cases often rely on observations, field sobriety tests, and toxicology reports, which can be much more subjective.

The Typical DUI Drug Investigation Includes:

• Traffic Stop or Incident: An officer observes erratic driving, speeding, or is called to the scene of an accident.
• Field Sobriety Tests (FSTs): These may include balance tests, coordination exercises, and eye examinations.
• Preliminary Breath Test (PAS): If the result is 0.00% or below 0.08% but the driver still appears impaired, officers may suspect drug use.
• Drug Recognition Expert (DRE): Some departments use specially trained officers to evaluate drivers for signs of drug impairment using a 12-step protocol.
• Blood Test or Urine Test: A chemical test is used to determine if any substances are present in the driver’s system.

Keep in mind: presence of a drug does not automatically mean you were impaired while driving. That’s a key argument we build into many successful defenses.

Common Substances Involved in DUID Cases

Some drugs more commonly lead to DUI charges, including:

• Marijuana (especially in combination with alcohol)
• Prescription opioids (e.g., Vicodin, Norco)
• Benzodiazepines (e.g., Valium, Ativan)
• Stimulants (e.g., Adderall, methamphetamine)
• Sleep medications (e.g., Ambien)
• Antihistamines and cold medications

Even CBD and THC-infused products can lead to a DUID arrest if police believe your driving was impaired.

Penalties for Driving Under the Influence of Drugs in California

DUID offenses under Vehicle Code § 23152(f) are generally prosecuted as misdemeanors, though certain factors can lead to felony charges.

First-Offense Misdemeanor DUID Penalties

• 3 to 5 years of probation
• Up to 6 months in county jail
• $390 to $1,000 in base fines (plus penalty assessments)
• Mandatory DUI education classes
• Driver’s license suspension for at least 6 months
• Possible requirement to install an ignition interlock device (IID)

Felony DUID Charges May Apply If:

• It’s your fourth or subsequent DUI within 10 years
• You have a prior felony DUI conviction
• You caused an accident that resulted in serious injury or death

Felony DUID consequences can include:

• 16 months to 3 years in state prison
• $1,000 to $5,000 in fines
• Formal probation
• License revocation

These penalties are harsh, but with the right defense, they are not inevitable.

Refusing a Chemical Test: What Happens?

Under California’s implied consent law, you must submit to a chemical test after a lawful DUI arrest. If you refuse:

• The DMV will automatically suspend your license for one year, even if you’re never convicted.
• The court may impose enhanced penalties if you are convicted of DUID.

If you’re on DUI probation or under age 21, refusing a test carries even more serious consequences.

Legal Defenses to DUID Charges

Drug DUI cases are highly complex and highly defensible. Unlike alcohol DUI, there’s no universally accepted measure of drug impairment. That gives your defense attorney multiple angles to challenge the case.

Possible Defenses Include:

1. You Weren’t Actually Impaired

Testing positive for a drug doesn’t mean it affected your ability to drive. Many drugs stay in your system long after the effects have worn off.

2. Flawed or Unreliable Drug Recognition Evaluation

The 12-step DRE protocol is not foolproof. Officers may misinterpret medical symptoms or fail to properly administer the tests.

3. Improper Collection or Handling of Blood Samples

California law requires strict procedures for storing and analyzing DUI blood samples (Title 17 of the California Code of Regulations). Any violation can lead to discrediting  the evidence.

4. You Have a Medical Condition

Conditions like fatigue, anxiety, or neurological disorders can mimic signs of drug impairment. Without proper medical context, officers may wrongly conclude that you were under the influence.

5. Unlawful Stop or Lack of Probable Cause

If police stopped you without a valid reason or arrested you without probable cause, any evidence gathered afterward may be inadmissible in court.

No “Per Se” Drug Limit: Why That Matters

One of the biggest challenges in DUID cases is the lack of a clear legal standard. While 0.08% BAC is the bright line for alcohol, there is no equivalent limit for drugs. Prosecutors must prove actual impairment.

Should You Take a Plea Deal for a DUID?

Sometimes, prosecutors may offer a wet reckless or a Health & Safety Code § 11550 (under the influence of a controlled substance) charge as an alternative to a full DUID conviction. Whether to accept a deal depends on the strength of the evidence and your specific circumstances.

Before making any decisions, it’s essential to consult with a skilled DUI defense attorney who can explain your options and negotiate on your behalf.

Arrested for Drug DUI in San Diego? Call Our Office Today.

At David P. Shapiro Criminal Defense Attorneys, we know how to attack the weaknesses in drug DUI investigations—and how to push for dismissals, reductions, or alternative sentencing when appropriate.

Call us now or visit https://www.davidpshapirolaw.com to schedule a confidential consultation with a top-rated San Diego DUI defense lawyer.

FAQs – California Vehicle Code § 23152(f)

Is it illegal to drive on prescription drugs in California?

Yes, if the drug affects your ability to drive safely, even with a valid prescription.

Can I be charged with DUI if I only used marijuana?

Yes. Even medical marijuana or legal recreational use can lead to DUI charges if you’re deemed impaired.

What happens if I refuse a blood test?

You may face automatic license suspension and enhanced penalties—even if you’re not convicted.

How long do drugs stay in your system?

It varies widely depending on the drug, dosage, frequency of use, and your body’s metabolism. Some drugs can be detected long after the effects have worn off.