DUI

What Is a DUI Under California Law?

California charges driving under the influence under Vehicle Code § 23152, which contains two separate subsections that are usually filed together:

VC 23152(a) — Driving under the influence of alcohol, drugs, or both. This subsection has no numeric threshold. The prosecution argues your ability to drive was impaired, and it can be proven through driving pattern, officer observations, and field sobriety tests even without a chemical result.

VC 23152(b) — Driving with a blood alcohol concentration of 0.08% or higher. This one is purely numeric. If the chemical test is unreliable, the charge is vulnerable.

Being charged under both isn’t double jeopardy. Prosecutors file them together so that if one theory fails, the other survives.

Different Limits for Different Drivers

DUI Causing Injury — VC 23153

When a DUI results in injury to another person, the charge becomes a wobbler under Vehicle Code § 23153 and can be filed as a felony. Exposure increases sharply with the severity of the injury and the number of people hurt.

Drug DUI

You can be charged with DUI for prescription medication, cannabis, or any substance that impairs driving — legality is irrelevant. Drug DUI cases are frequently weaker than alcohol cases because there is no equivalent of a per se limit and no reliable roadside test.

The Two Cases Against You

Most people don’t realize a DUI arrest triggers two entirely separate proceedings.

The criminal case is filed by the District Attorney and decides guilt, jail exposure, fines, probation, and DUI school.

The DMV case is an administrative proceeding that decides only one thing: whether you keep your license. It has its own hearing, its own rules of evidence, and a lower standard of proof. It moves faster than the criminal case and is decided by a DMV hearing officer, not a judge.

Winning one does not automatically win the other. Both have to be defended.

→ Learn more about DMV Hearings

What the Prosecution Has to Prove

For a VC 23152(b) charge, the prosecution must prove beyond a reasonable doubt that:

1. You drove a vehicle; and
2. Your blood alcohol concentration was 0.08% or more at the time you were driving.

That last phrase carries the case. Chemical tests are administered at the station, often an hour or more after the stop. The prosecution has to connect that later reading back to the moment you were behind the wheel — and alcohol absorption doesn’t cooperate with that assumption.

For a VC 23152(a) charge, the prosecution must prove you drove while your mental or physical abilities were impaired to the point you couldn’t drive with the caution of a sober person. That’s a subjective standard built largely on the arresting officer’s opinion.

DUI Penalties in California

First Offense (Misdemeanor)

• County jail exposure
• Fines plus substantial penalty assessments, which multiply the base fine several times over
• 3 to 9 month DUI education program
• License suspension
• Informal probation, typically 3 to 5 years
• Ignition interlock device requirement

Second and Third Offenses

Penalties escalate significantly within the 10-year lookback period — longer mandatory jail terms, extended DUI programs, longer suspensions, and mandatory interlock installation.

When a DUI Becomes a Felony

A DUI can be charged as a felony when:

• It is a fourth or subsequent DUI within 10 years
• It caused injury to another person (VC 23153)
• You have a prior felony DUI conviction
• Someone died — which can support gross vehicular manslaughter or, with a prior DUI and a Watson admonition on record, a murder charge

Consequences Beyond Sentencing

• Insurance. An SR-22 filing is typically required, and premiums often increase substantially for years.
• Employment. DUI convictions appear on background checks and can disqualify commercial drivers, healthcare workers, and license holders.
• Immigration. Multiple DUIs or a DUI with aggravating factors can carry immigration consequences.
• Professional licensing. Many boards require self-reporting.
• Record. A California DUI stays on your driving record for 10 years and on your criminal record indefinitely unless expunged.

→ Expungements

Defenses to DUI Charges

DUI cases look airtight because they come with a number attached. That number is produced by machines, procedures, and human judgment, and every one of those can fail.

The traffic stop was unlawful. Officers need reasonable suspicion to pull you over. Weaving within your lane, a hunch, or an anonymous tip may not be enough. If the stop was unlawful, everything that followed can be suppressed.

Rising blood alcohol. Alcohol continues to absorb after your last drink. A reading of 0.09% taken 75 minutes after the stop is entirely consistent with being under 0.08% while actually driving — and the law measures the moment you drove, not the moment you blew.

The breath machine wasn’t reliable. California’s Title 17 regulations govern calibration intervals, observation periods, and operator training. Machines drift, logs go unmaintained, and observation periods get shortened. Every one of those is discoverable.

Medical and dietary conditions. GERD, acid reflux, and diabetes can produce mouth alcohol or ketones that inflate a breath reading without any corresponding blood alcohol level. Low-carbohydrate diets can do the same.

Field sobriety tests are unreliable. Only three are standardized, and even those were validated under conditions that rarely match a real roadside stop. Weight, age, injury, footwear, uneven pavement, and traffic all affect performance in ways that have nothing to do with alcohol.

Blood draw problems. Improper storage, fermentation, chain-of-custody gaps, and unqualified technicians all give grounds to challenge a blood result. The sample can often be independently retested.

You weren’t driving. The prosecution has to prove actual driving — an issue in cases involving parked cars, accidents with no witnesses, and passenger disputes.

Related Charges

• DMV Hearings — the administrative license case
• Driving on a Suspended License — VC 14601
• Hit and Run — VC 20001
• Vehicular Manslaughter — PC 191.5
• Drug Crimes — for drug-related DUI arrests
• Expungements — clearing a prior DUI conviction

Why a Former Prosecutor Matters in a DUI Case

DUI is the highest-volume case in any District Attorney’s office, which means it’s also the most routine — handled fast, on a template, with heavy reliance on the arrest report and the chemical result.

Polina Logrue filed and tried these cases at the Orange County District Attorney’s Office. She knows which arrest reports get scrutinized and which get taken at face value, what makes a prosecutor reconsider a filing, and where the office has room to negotiate a reduction to a wet reckless or a dismissal.

Routine cuts both ways. A case handled on a template has gaps in it.

Meet Polina →

Arrested for DUI? Start With These Steps

1. Request your DMV hearing within 10 days. This is the deadline that can’t be recovered.
2. Don’t discuss the arrest with anyone other than your attorney.
3. Write down everything you remember — what you ate and drank and when, how long you waited, what the officer said, who else was present.
4. Keep every document you were given, including the pink temporary license.
5. Call an attorney before your arraignment.

Call (949) 758-4469 · Free Consultation