DUI Causing Injury in California: What Must Be Proven?

If someone else was hurt in your crash, the charge can sound almost self-proving: there was a collision, the police suspect DUI, and another person received medical care. It can feel as though the only thing left to settle is what happens to you. California law does not combine those facts into one conclusion.

Under Vehicle Code section 23153 (opens in a new window), the prosecution must prove the applicable DUI theory. It must also prove that, while driving, you committed another act forbidden by law or neglected a legal duty. That act or neglect must have caused bodily injury to someone other than the driver.

Your case therefore turns on a chain, not a label: the DUI allegation, the additional driving conduct, the collision, causation, and injury. A reported test result may matter greatly without answering every question in that chain.

Four parts have to connect, and evidence in each one is not enough.

The exact DUI theory depends on the subsection charged. A complaint may allege impairment by alcohol, a prohibited alcohol concentration, impairment by a drug, or the combined influence of alcohol and a drug. More than one count can arise from the same driving event, but each theory still has elements the prosecution must prove.

The remaining parts are sometimes compressed into the phrase “an injury accident.” That shorthand hides the questions that often matter most in your case:

The prosecution must prove the connected theory, not merely place evidence in each category. A chemical result does not explain how a crash occurred. An injury does not establish impairment. A traffic mistake does not automatically show that the mistake caused the claimed harm.

The additional driving act cannot simply be the DUI itself.

The prosecution must identify conduct beyond driving under the influence. It may allege an act forbidden by law, such as an unsafe movement or another traffic violation. It may instead allege neglect of a legal duty, such as a failure to use ordinary care under the circumstances.

California's 2026 criminal jury instructions for section 23153 require the jury to be told what unlawful act or neglected duty is alleged. When the theory is negligence, the instructions describe the driver's duty to use reasonable care to avoid foreseeable harm. The DUI allegation itself cannot serve as the separate unlawful act. So the question is bigger than whether you were impaired. It's what else the prosecution says you did behind the wheel.

That distinction changes how you should read the reports in your case. If the complaint or the reports say only that you were impaired and a collision followed, the missing question is what particular driving conduct allegedly connects the two. If several drivers, a road condition, a signal sequence, or an unexpected event contributed, the chronology matters more than an officer's broad conclusion.

Causation starts with a reliable timeline, not with someone's conclusion.

Build the sequence from sources created close to the event: dispatch and 911 records, body-camera and dash-camera video, traffic-camera or nearby surveillance footage, vehicle positions, photographs, measurements, electronic vehicle data when available, and witness accounts. Medical timing may help identify when symptoms or treatment began, but it does not reconstruct the collision by itself.

The order of events matters. Which vehicle entered the intersection first? What did the signal show? When did braking or steering begin? Was there a second impact? Could a witness actually see the critical movement? Did a later report repeat someone else's assumption as though it were direct observation?

Small timing differences can change the causal analysis. They can also reveal that two statements that sound compatible in summary cannot both describe the same sequence.

Proximate cause is more precise than asking who was at fault.

The jury instructions distinguish between a single-cause and a multiple-cause case. In a single-cause theory, the alleged act must be a direct, natural, and probable cause of the injury, and the injury would not have happened without it. When several causes operate at the same time, the accused person's conduct need not be the only cause, but it must be a substantial factor—more than something trivial or remote.

That means another driver's conduct does not automatically end the prosecution's case. It also means the government cannot satisfy causation merely by showing that you were present, allegedly impaired, and involved in the crash. The question is whether the separately alleged act or neglected duty substantially contributed to the injury under the facts the evidence can support.

The analysis should distinguish a true intervening event from an ordinary contributing cause. It should also avoid reconstructing a collision from hindsight. The relevant question is what the evidence shows happened, not what seems obvious after knowing that someone was hurt.

An injury to you is not the injury this charge requires.

Section 23153 requires bodily injury to a person other than the person accused of the DUI. The injured person may be an occupant of another vehicle, a passenger, a pedestrian, or another person affected by the event. The statute does not require the injured person to have been driving.

The identity and location of each person should be clear in the record. In a multi-vehicle collision, the reports you are handed may use labels such as “P-1” or “passenger two” inconsistently. Ambulance records, body-camera footage, photographs, and the collision diagram can help connect the person, vehicle, and claimed injury without assuming that every medical record belongs to the same individual.

“Great bodily injury” is a separate allegation, not a louder word for the same thing.

Section 23153 uses the term “bodily injury.” A complaint may also contain a separate great-bodily-injury allegation under Penal Code section 12022.7 (opens in a new window). That statute defines great bodily injury as significant or substantial physical injury, but the allegation has additional requirements and limits that must be reviewed from the actual charging document.

The two should not be treated as synonyms. Medical records, imaging, treatment notes, and testimony may bear on both, but the legal questions are not identical. Nor should the seriousness of an injury be used to skip the earlier causation question. The prosecution must still connect the charged driving conduct to the harm.

Whether the injury allegation makes a particular DUI filing felony-capable is a related classification question. When Can a DUI Be Charged as a Felony in California? explains the statutory routes without treating the filing label as the outcome.

The crash does not prove the DUI by itself.

Even when the collision and injury evidence are substantial, the government must still prove the charged alcohol, drug, or combined-influence theory. The review in your case may include the identity of the driver, the quality of the driving observations, video, the time of any breath or blood collection, instrument or laboratory records, sample handling, medical treatment, and the foundation for opinion testimony.

The manner of driving can be considered as part of an impairment case, but the California jury instructions caution that it is not enough by itself to establish that a person was under the influence. A collision can result from many causes. The prosecution's impairment evidence and its collision-causation evidence should be examined together without allowing one to stand in for the other.

For a broader discussion of testing, video, reports, and laboratory records, see What Evidence Can Be Challenged in a California DUI Case?.

Preserve the collision record before it changes or disappears.

Keep the citation, complaint, release papers, DMV notice, police reports, photographs, medical releases or bills already in your possession, and all correspondence. Write down where nearby cameras were located and whether anyone mentioned a recording. Preserve existing phone photographs, messages, and location records; do not edit them or create a new account designed to fill gaps.

Vehicles may be repaired, roadway conditions change, and privately held video may be overwritten. An attorney can determine which preservation or discovery steps are lawful and appropriate. The DUI arrest-response guide explains how to organize the immediate court and DMV papers while the evidence review begins.

Official Sources

• California Vehicle Code § 23153 (opens in a new window)
• California Penal Code § 12022.7 (opens in a new window)
• Judicial Council of California: 2026 Criminal Jury Instructions (opens in a new window)

Trace the alleged injury back through the collision.

Bring the complaint, reports, photographs, known video information, medical records already available to you, and a careful event timeline to a case-specific review. The first job is not to decide how the case ends. It's to identify the charged DUI theory, the additional act or neglected duty, and the evidence said to connect that conduct to another person's injury.

Boyadzhyan Legal Shield's criminal-defense practice includes California DUI defense. A free, confidential initial consultation carries no obligation to hire the firm. You can request a consultation or learn more about California DUI defense.

This article provides general information, not legal advice. The charged subsection, causation, medical proof, and any great-bodily-injury allegation require current, case-specific review by a California attorney.