## Facts

- The Trull family traveled in New Hampshire in a Volkswagen Vanagon that slid on black ice and collided with an oncoming vehicle.
- Two children, Nathaniel and Benjamin, rode on a rear middle bench seat equipped with lap-only seatbelts and wore the available lap belts.
- Benjamin died; Elizabeth and Nathaniel sustained severe brain injuries.
- The Trulls sued Volkswagen in a federal diversity action asserting crashworthiness (enhanced-injury) claims, alleging design defects made the injuries worse than they otherwise would have been.
- The alleged defects included (1) inadequate frontal-impact protection due to a forward-control vehicle design and (2) failure to equip the rear bench seat with shoulder belts in addition to lap belts.
- At trial, the jury was instructed that plaintiffs had to prove not only causation but also the specific nature and extent of injuries enhanced by the alleged defects; the jury found for Volkswagen.
- On appeal, the First Circuit certified to the New Hampshire Supreme Court the question of who bears the burden to apportion damages between initial-collision injuries and defect-enhanced injuries.

## Issues

1. In a crashworthiness/enhanced-injury case under New Hampshire law, must the plaintiff prove the specific nature and extent of injuries attributable to the alleged defect, or does the burden shift to the defendant to apportion damages once causation is shown?

## Decision

- The New Hampshire Supreme Court answered the certified question by adopting a burden-shifting rule for crashworthiness cases involving indivisible injuries.
- Plaintiffs must prove the alleged design defect was a substantial factor in producing damages beyond those probably caused by the original collision.
- Once plaintiffs make that showing, the burden shifts to the defendant to prove which injuries are attributable to the initial collision and which are attributable to the defect.

## Legal Principles

- Crashworthiness (enhanced-injury) liability addresses defects that do not cause the accident but allegedly increase the severity of harm.
- In cases of indivisible injury, the plaintiff’s required showing is enhanced-injury causation: the defect must be a substantial factor in producing additional harm beyond the original impact.
- After substantial-factor enhanced-injury causation is established, the defendant bears the burden of apportioning damages between accident-caused injuries and defect-enhanced injuries.
- If apportionment cannot be made, the risk of non-apportionment falls on the defendant after the plaintiff meets the causation threshold.

## Conclusion

The court held that in New Hampshire crashworthiness cases involving indivisible injuries, plaintiffs need only prove that a design defect substantially contributed to additional harm beyond the initial collision; the manufacturer then bears the burden to apportion damages between collision injuries and defect-enhanced injuries.


Trull v. Volkswagen of Am., Inc., 761 A.2d 477 (N.H. 2000)