Vehicle Code 23152(a) is the other half of almost every California alcohol DUI. While 23152(b) is about a number, 23152(a) is about impairment. It makes it a crime to drive while under the influence of alcohol, with no fixed BAC required. I am Joel Brand, and this is the charge that controls the cases with a low or refused test, a drug or alcohol-plus-drug DUI, or a number the prosecutor is worried they cannot prove.

Vehicle Code 23152(a). It is unlawful for a person who is under the influence of any alcoholic beverage to drive a vehicle.

What "under the influence" actually means

"Under the influence" does not mean you had a drink. It means your physical or mental abilities were impaired to the point that you could no longer drive with the caution of a sober person using ordinary care under similar circumstances. There is no magic BAC. You can be convicted under 23152(a) with a BAC under 0.08 percent if the prosecutor can show impairment, and you can beat it at a higher number if the impairment evidence is weak.

One rule cuts the other way: if your BAC was 0.08 percent or more, the law lets the jury presume you were under the influence. That presumption can be rebutted, but it is why this charge is almost always filed alongside the per se charge under 23152(b).

What the prosecutor has to prove

  1. You drove a vehicle. Direct evidence (an officer saw you drive) or circumstantial evidence (you were in the driver's seat of a running car). When nobody saw the car move, I attack the driving element directly. See the "no driving" defense.
  2. You were under the influence of alcohol when you drove. The state leans on the officer's observations, your statements, and field sobriety tests. Every one of those is subjective and challengeable.

Penalties for a first 23152(a) conviction

A first 23152(a) with no injury and no priors is a misdemeanor, and the sentence mirrors the per se charge. With probation, which is the usual outcome, you are typically looking at:

  • Fine: $390 to $1,000 base under Vehicle Code 23538, plus court assessments that multiply the total. Estimate it with my total DUI cost calculator.
  • DUI program: a 3-month, 30-hour program, or a 9-month, 60-hour program for a high BAC or a refusal.
  • Probation: three to five years of informal probation.
  • Jail: with probation, 48 hours to 6 months is available as a condition and is often minimal or waived for a true first offense. Without probation, Vehicle Code 23536 sets a 96-hour minimum.
  • License: a conviction triggers a 6-month court suspension. Separately, the DMV imposes a 4-month administrative suspension if a chemical test showed 0.08 percent or more. An ignition interlock device usually lets you keep driving throughout. The full license picture is in my California DUI license guide.

Penalties rise with a prior, a high BAC, a child passenger, or an injury. See the California DUI penalties guide and, if anyone was hurt, DUI causing injury under VC 23153.

How I defend a 23152(a) charge

Because 23152(a) turns on impairment, not a number, the fight is over the human evidence:

  • The stop and arrest. No reasonable suspicion to stop, or no probable cause to arrest, and the evidence can be suppressed. See my top DUI defenses.
  • Field sobriety tests. These are scored on the officer's opinion and are affected by nerves, footwear, road conditions, weight, age, and injury. See the unfair field sobriety test defense.
  • Innocent explanations for "objective signs." Red eyes, slurred speech, and poor balance have many causes other than alcohol, including fatigue, allergies, and medical conditions.
  • The number does not match the driving. A clean driving pattern and a low BAC undercut the claim of impairment, which opens the door to a reduction such as a wet reckless. Gauge your odds with my wet reckless calculator.

Why prosecutors file 23152(a) and (b) together

In almost every alcohol DUI you will see two counts on the complaint: 23152(a) for being under the influence and 23152(b) for driving with a BAC of 0.08 percent or more. This is not double-charging in the sense of double punishment, because you can only be punished once for a single act of driving. It is a strategic choice that gives the prosecutor two independent paths to a conviction. If the chemical number gets thrown out because the machine was unreliable or the blood was mishandled, the (a) count survives on the officer's observations. If the impairment evidence looks thin, the (b) count still rests on the number. Understanding this is key, because a complete defense has to address both theories, not just the one that seems strongest.

The driving-pattern evidence cuts both ways

Because 23152(a) is about impairment, how you were actually driving becomes important evidence. Prosecutors point to weaving, speeding, or an accident as signs of impairment. But the reverse is just as powerful for the defense: a clean driving pattern, a minor equipment violation as the only reason for the stop, and a calm, coherent interaction with the officer all undercut the claim that you were too impaired to drive safely. I look closely at the dash-cam and the stated reason for the stop, because a sober-looking driving pattern is often the best answer to an impairment charge, especially when the test number is low or contested.

Drugs, prescriptions, and combined-influence cases

Section 23152(a) also reaches driving under the influence of drugs or a combination of drugs and alcohol, which makes it the charge in cases where there is no breath number, where the substance is a prescription medication, or where the officer suspects something beyond alcohol. These cases lean heavily on a drug recognition evaluation and blood testing, both of which have real weaknesses. Whether a measured level actually proves impairment at the time of driving is frequently the central fight, and it is far less settled than the prosecution suggests.

Two deadlines start at the arrest

You have just 10 days to demand a DMV hearing before the administrative suspension takes effect on its own. The criminal case is separate. Both should be handled together from the start. See the first 10 days after a DUI and run your numbers through the DMV hearing deadline calculator.

Charged under 23152(a)? Let's talk.

An impairment charge lives or dies on subjective evidence, and subjective evidence can be challenged. California DUI defense is my entire practice. Use the free case analysis on this page, or call me directly at (888) 271-6644. I answer my own phone, 24/7.