Strict Products Liability

Strict products liability imposes liability on commercial sellers and manufacturers for physical harm caused by products that are defective and unreasonably dangerous, without requiring the plaintiff to prove negligence. The doctrine was established by the California Supreme Court in Greenman v. Yuba Power Products (1963) and codified in the Restatement (Second) of Torts Section 402A.

A product may be defective in three ways. A manufacturing defect exists when a particular unit departs from the intended design — it differs from otherwise identical products coming off the same production line. A design defect exists when the entire product line is unreasonably dangerous because the manufacturer could have adopted a reasonable alternative design that would have reduced the risk. The consumer expectations test and the risk-utility balancing test are the two predominant approaches to evaluating design defects. A warning or marketing defect exists when the product lacks adequate instructions or warnings about risks that are not obvious to the ordinary user.

The doctrine eliminated the privity requirement that had historically limited product liability claims. Under MacPherson v. Buick Motor Co. and its progeny, a manufacturer owes a duty of care to the ultimate consumer regardless of whether they are in a direct contractual relationship. Strict products liability extends this principle by removing the need to prove negligence at all — the plaintiff need only show that the product was defective, the defect existed when it left the defendant's control, and the defect caused the plaintiff's injury.

Policy justifications for strict products liability include loss spreading (manufacturers can distribute costs through insurance and pricing), incentivizing safety (manufacturers are in the best position to identify and eliminate defects), and consumer protection (individual consumers cannot adequately assess complex product risks). The doctrine applies to all commercial sellers in the chain of distribution, including manufacturers, wholesalers, and retailers.