Mildred Sandford (plaintiff) suffered serious injuries and burns when the truck that she was driving overturned and caught fire. Sandford filed a negligence action, grounded in products liability, against the manufacturer of the truck (the Chevrolet Division of General Motors Corporation), the manufacturer of the tires mounted on the truck (Uniroyal, Inc.), and the company that mounted the tires on the truck (The Tire Factory) (defendants). Sandford argued that the accident was caused by a defective tire manufactured by Uniroyal and mounted onto the truck by The Tire Factory. The defendants claimed that Sandford’s own negligence caused the accident. The jury apportioned fault as follows: Uniroyal and The Tire Factory were 55 percent at fault, and Sandford was 45 percent at fault. The jury awarded Sandford a fraction of her total damages. The defendants appealed. The court of appeals reversed and held that, under the state’s proportionate-fault statute, a plaintiff’s recovery of damages for injuries caused by a defective product could not be reduced by the plaintiff’s ordinary negligence. The Supreme Court of Oregon granted certiorari to review.