It doesn’t take much for a young driver to get into legal trouble when alcohol is involved. In California, the law is clear: if you’re under 21 and drinking, you shouldn’t be driving—period. And the state’s zero-tolerance approach means that even a tiny amount of alcohol in your system can lead to a DUI.
If your child has been charged with underage DUI, or you’re a young adult facing a DUI arrest yourself, understanding your rights is the first step toward protecting your future.
What Is California’s Zero Tolerance Law?
Under California Vehicle Code § 23136, drivers under the age of 21 are subject to what’s called the “zero tolerance” law. That means:
- A blood alcohol concentration (BAC) of just 0.01% or more is enough for a DUI-related offense
- Even one drink can trigger a violation
This isn’t the same as a standard DUI, which requires a BAC of 0.08% or higher. But the penalties for violating the zero-tolerance law can still be serious, especially for a teen or young adult who’s just starting out in life.
How Underage DUI Is Charged in California
There are actually a few different charges a young driver might face after being stopped:
- Zero Tolerance Violation (§ 23136) – BAC of 0.01% or higher
- Civil offense, not criminal
- Typically results in a 1-year license suspension.
- Underage DUI (§ 23140) – BAC of 0.05% to 0.07%
- Infraction, not a misdemeanor
- Penalties may include fines, license suspension, and mandatory DUI education.
- Standard DUI (§ 23152) – BAC of 0.08% or more, or impairment due to alcohol or drugs
- Charged the same way as an adult DUI
- Criminal offense with potential for jail time, probation, and a permanent record
In some cases, a young driver may be charged under multiple sections of the law, especially if drugs are involved or if the stop involved reckless driving or an accident.
What Are the Penalties for an Underage DUI?
Even without a criminal conviction, the consequences of an underage DUI can be long-lasting. Depending on how the case is charged, a young driver could face:
- Suspension of their driver’s license for 1 year or more
- Fines and court fees
- Mandatory DUI school or alcohol education classes
- Community service=
- Increased car insurance costs—or loss of coverage altogether
And then there’s the bigger picture: a mark on your record at 18 or 19 can affect college admissions, job prospects, and eligibility for scholarships or financial aid.
What Happens After an Arrest?
After a DUI stop involving someone under 21, there are two paths the case can take:
- Administrative license action through the DMV: The driver has just 10 days to request a hearing, or their license will be automatically suspended.
- Criminal or civil court proceedings: Depending on the BAC and other circumstances, the case may proceed in juvenile court, traffic court, or criminal court.
Parents are often shocked by how quickly things move. That’s why it’s so important to talk to an attorney as soon as possible—before key deadlines are missed.
Are There Defenses to an Underage DUI?
Yes. Just because someone is under 21 and pulled over after drinking doesn’t mean the case is unbeatable. Possible defenses include:
- Faulty breath test results (especially at very low BAC levels)
- Improper stop (no reasonable suspicion to pull over)
- Lack of proof of driving
- Rising BAC (the alcohol wasn’t fully absorbed until after the stop)
- Violation of search and seizure rights
Every case is different, and the facts matter. An experienced attorney can help determine the best course of action—whether that means fighting the charges or negotiating for a reduced penalty.
Talk to a Contra Costa County Underage DUI Defense Lawyer Today
California takes underage drinking and driving seriously, but that doesn’t mean young people should be judged for a mistake. At The Law Offices of Johnson & Johnson, we work closely with teens, young adults, and their families to defend against DUI charges and limit long-term consequences. Contact us today to schedule a complimentary consultation.