PERSONAL INJURY | 2026-09-29
Negligence Per Se in California: Using a Statutory Violation to Prove Fault (Evidence Code § 669)
When a defendant breaks a safety law and that violation causes the kind of harm the law was meant to prevent, California lets you presume negligence. Here are the four elements of negligence per se.
Proving negligence usually means showing the defendant failed to act as a reasonable person would. But when a defendant violated a statute, ordinance, or regulation designed to protect against the very harm that occurred, California law lets the plaintiff take a shortcut: negligence per se. Under Ev
A statute broken, an injury caused. California’s negligence per se doctrine turns certain legal violations into a presumption of negligence, sparing the plaintiff from proving the reasonableness question from scratch.
What Negligence Per Se Is
Negligence per se is not a separate cause of action; it is an evidentiary presumption within a negligence claim. When it applies, the defendant’s violation of a law establishes the breach-of-duty element, so the jury presumes the defendant was negligent. The plaintiff still must prove that the violation was a cause of the injury and that they suffered damages.
The Four Elements — Evidence Code § 669
Under Evidence Code § 669, a presumption of negligence arises if the plaintiff establishes all four of the following:
- the defendant violated a statute, ordinance, or regulation;
- the violation proximately caused the death or injury;
- the injury resulted from an occurrence of the nature the law was designed to prevent; and
- the injured person was one of the class of persons for whose protection the law was adopted.
The last two elements — the type-of-harm and class-of-persons tests — are what keep the doctrine tied to the law’s purpose. A violation of a law meant to prevent a different kind of harm, or to protect a different group, does not create the presumption.
How Defendants Rebut It
Even when the four elements are met, the presumption is rebuttable in defined ways. Evidence Code § 669 recognizes that the presumption may be overcome by proof that the violator did what might reasonably be expected of a person of ordinary prudence, acting under similar circumstances, who desired to comply with the law — for example, where compliance was impossible or an emergency (not of the violator’s making) prevented it, or where the violation was reasonable because of the actor’s incapacity. Absent such a showing, the presumption stands.
Common Applications
Negligence per se frequently appears where a defendant violated a Vehicle Code provision (speeding, running a red light, unsafe lane change) and caused a collision, or violated a safety code or regulation that led to injury. In those cases, proving the violation can establish breach, letting the plaintiff concentrate on causation and damages.
Frequently Asked Questions
Does negligence per se automatically win my case?
No. It presumes the breach element from a statutory violation, but you still must prove causation and damages, and the presumption can be rebutted.
What are the four elements?
A violation of a law; the violation proximately caused the injury; the injury is of the type the law was meant to prevent; and the plaintiff is in the class the law protects (Evid. Code § 669).
Can the defendant overcome the presumption?
Yes — by showing they did what a reasonably prudent person desiring to comply would have done under the circumstances (e.g., compliance was impossible or prevented by an emergency not of their making).
Where is it used most?
Often in vehicle-code-violation collisions and safety-regulation cases, where proving the violation establishes breach.
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Talk to a California Personal Injury Attorney
If a defendant broke a safety law and hurt you, negligence per se may establish their fault. Trembach Law Firm uses and defends the doctrine in California injury cases. Call (818) 514-7680.
Contact Trembach Law Firm at (818) 514-7680 for a confidential consultation.
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