CACI 712 Affirmative Defense—Failure to Wear a Seat Belt

California Civil Jury Instructions CACI

712 Affirmative Defense—Failure to Wear a Seat Belt


[Name of defendant] claims that [name of plaintiff] was negligent because [he/she/nonbinary pronoun] failed to wear a seat belt. To succeed, [name of defendant] must prove all of the following:

1.That a working seat belt was available;

2.That a reasonably careful person in [name of plaintiff]’s situation would have used the seat belt;

3.That [name of plaintiff] failed to wear a seat belt; and

4.That [name of plaintiff]’s injuries would have been avoided or less severe if [he/she/nonbinary pronoun] had used the seat belt.

[In deciding whether a reasonably careful person would have used a seat belt, you may consider Vehicle Code section 27315, which states: [insert pertinent provision].]


Directions for Use

Note that the Motor Vehicle Safety Act (Veh. Code, § 27315) applies only to persons 16 years or older. (Veh. Code, § 27315(d)(1).) No case law regarding whether persons under 16 can be found comparatively negligent for failing to wear a seat belt has been found.


Sources and Authority

Failure to Wear Seat Belt as Negligence. Vehicle Code section 27315(i).

“Defendants … are required to prove two issues of fact: (1) the defendant must show whether in the exercise of ordinary care the plaintiff should have used the seat belt which was available to him. … (2) The defendant must show what the consequence to the plaintiff would have been had seat belts been used.” (Franklin v. Gibson (1982) 138 Cal.App.3d 340, 343 [188 Cal.Rptr. 23].)

“Upon a retrial the court or jury will determine whether in the exercise of ordinary care [plaintiff] should have used the seat belt; expert testimony will be required to prove whether [plaintiff] would have been injured, and, if so, the extent of the injuries he would have sustained if he had been using the seat belt … .” (Truman v. Vargas (1969) 275 Cal.App.2d 976, 983 [80 Cal.Rptr. 373].)

In Housley v. Godinez (1992) 4 Cal.App.4th 737, 747 [6 Cal.Rptr.2d 111], the court approved of the following jury instruction, which was read in addition to section 27315: “The Defendants have raised the seat belt defense in this case. First, you must decide whether in the exercise of ordinary care, the Plaintiff should have used seat belts, if available to him. Second you must determine with expert testimony the nature of injuries and damages Plaintiff would have sustained if he had used seat belts.”

“[Section 27315] permits the civil trial courts to instruct on the existence of the seat belt statute in appropriate cases, while allowing the jury to decide what weight, if any, to give the statute in determining the standard of reasonable care.” (Housley, supra, 4 Cal.App.4th at p. 747.)

“[N]othing in the statute prohibits a jury from knowing and considering its very existence when determining the reasonableness of driving without a seat belt.” (Housley, supra, 4 Cal.App.4th at p. 744.)

“There was evidence presented that appellant’s failure to wear a seat belt worsened his injuries. The foreseeability test clearly eliminates this act as a supervening cause because it is the general likelihood of the type of injury that must be unforeseeable in order to absolve defendant; the extent of injury need not be foreseeable.” (Hardison v. Bushnell (1993) 18 Cal.App.4th 22, 28 [22 Cal.Rptr.2d 106].)

“Expert testimony is not always required to prove that failure to use a seat belt may cause at least some, if not all, of plaintiff’s claimed injuries. [¶] Depending on the facts of the case, expert testimony may be necessary for the jury to distinguish the injuries that [plaintiff] unavoidably sustained in the collision from the injuries he could have avoided if he had worn a seat belt.” (Lara v. Nevitt (2004) 123 Cal.App.4th 454, 458–459 [19 Cal.Rptr.3d 865], internal citation omitted.)

“The seat belt defense does not depend on a Vehicle Code violation nor is it eviscerated by a Vehicle Code exemption from the requirement to wear seat belts.” (Lara, supra, 123 Cal.App.4th at p. 461 fn. 3.)


Secondary Sources

California Tort Guide (Cont.Ed.Bar 3d ed.) § 4.71
2 Levy et al., California Torts, Ch. 20, Motor Vehicles, § 20.05[2] (Matthew Bender)
8 California Forms of Pleading and Practice, Ch. 82, Automobiles: Causes of Action, § 82.10 (Matthew Bender)
California Civil Practice: Torts §  25:26 (Thomson Reuters)