A Driver Ran a Red Light and Hit You. California's negligence per se doctrine applies directly.

Red Light Accidents Under California Law

Violation of California Vehicle Code § 21453 — running a red light — triggers negligence per se under Evidence Code § 669, creating a presumption that the violating driver was negligent in causing the intersection crash.

California Vehicle Code § 21453(a) requires drivers to stop at red signals and remain stopped until a green signal is displayed. Running a red light — proceeding through an intersection against a steady or flashing red signal — is a moving violation that directly supports civil liability when it causes a collision.

Red light collisions are among California's most dangerous intersection crashes. Side-impact (T-bone) crashes from red light violations frequently involve direct force to the door area, causing serious injuries to occupants — including fractured ribs, abdominal trauma, thoracic spine injuries, and traumatic brain injury.

Proof that the other driver ran the red light typically requires: the police report (especially any citation), red light camera footage from the intersection (if available), witness statements, dashcam footage, and the physical evidence of the collision (a T-bone crash pattern strongly suggests intersection fault).

What to Do After a Red Light Accident in California

Steps to preserve the intersection-specific evidence — red light camera footage, witness accounts, and collision pattern evidence — that is most important in red light cases.

1
Call 911 immediately. A police report documenting that the other driver ran the red light — including any citation — is the most important single piece of evidence in your case.
2
Ask about red light cameras. Note whether there is a red light camera system at the intersection. City and county traffic enforcement cameras may have captured the light phase and vehicle position. Request from the traffic department promptly — footage retention is often 30 days or less.
3
Photograph all vehicle positions before they are moved. The post-crash positions of both vehicles, the collision damage pattern, and the surrounding intersection establish the collision geometry — all consistent with (or inconsistent with) a red light violation.
4
Collect all witness information. Other drivers at the intersection who witnessed the light phase and the other driver's failure to stop are essential witnesses. Get names, phone numbers, and addresses.
5
Seek prompt medical attention. T-bone collisions cause serious trauma. Medical documentation establishes the causal link between the crash and your injuries.
6
Preserve all evidence and records. Save the police report, all medical records, bills, and insurer correspondence. Do not post about the accident on social media.

Your Legal Rights After a Red Light Accident

Right to the Negligence Per Se Presumption

When the other driver violated CVC § 21453, Evidence Code § 669 entitles you to argue that negligence is presumed — you do not need to separately prove that running a red light was unreasonable. The presumption shifts the burden to the defendant to rebut negligence.

Right to Full Compensatory Damages

You are entitled to recover all economic damages (medical expenses, lost wages, property damage) and non-economic damages (pain and suffering, emotional distress) caused by the red light violation. California imposes no cap on compensatory damages in automobile accident cases.

Right to Recovery Despite Comparative Fault

California's pure comparative fault system (Civil Code § 1714) allows recovery even if you contributed to the accident. If you entered the intersection on a late yellow or had some other contributing factor, your damages are reduced proportionally — not eliminated.

Fault Determination in Red Light Accident Cases

Red light fault cases center on one factual question: what was the light phase when each vehicle entered the intersection? This is established through red light camera footage (most definitive), witness testimony, the police report, and accident reconstruction. When camera footage shows the at-fault driver entering against a red signal, the negligence per se argument is nearly conclusive.

Common defenses in red light cases include: (1) the light was yellow when I entered, (2) my brakes failed, (3) the plaintiff also entered on a red or yellow signal. Each defense involves different evidence. The intersection's signal timing data (obtainable from the city or county traffic engineering department) may establish whether a driver's claimed yellow light entry is consistent with the recorded timing cycle.

Insurance in Red Light Accident Cases

Red light accident claims proceed against the at-fault driver's liability insurer. When a police citation was issued for running the red light, insurers often accept liability quickly — the citation is strong evidence and many insurers do not contest clear statutory violations. If the at-fault driver's limits are insufficient, your UIM coverage (Insurance Code § 11580.2) provides additional recovery.

Evidence That Matters in Red Light Accident Cases

Key evidence: police report and any citation, red light camera footage (request from city/county traffic engineering department), dashcam footage, witness statements about the light phase, collision geometry photographs (T-bone pattern), and intersection signal timing data from the local traffic engineering department. Red light camera footage is the strongest possible evidence — request it within days of the crash.