The Principles of Product Liability, in Symposium, Products Liability: Litigation Trends on the 10th Anniversary of the Third Restatement

I. INTRODUCTION More than any other area of tort law, the law of product liability has been the subject of continuing debate regarding the interrelated issues of its proper rationales and grounds of liability. Although the seeds of the debate go back at least 100 years, it flowered into its mature form in 1944 in Escola v. Coca Cola Bottling Co.,1 in which the majority of the California Supreme Court used an expansive application of the res ipsa loquitur doctrine to hold the defendant liable for inferred negligence.2 In a concurring opinion, Justice Roger Traynor relied on four different rationales-efficient compensation, efficient deterrence, inferred negligence, and consumer expectations3-to argue that liability for defective products should be strict.4 Almost twenty years later, in 1963, Traynor's rationales and position were ratified and adopted in an opinion that he wrote for a unanimous court in Greenman v. Yuba Power Products, Inc.5 The Greenman opinion was a catalyst for the adoption of strict product liability, based on the same rationales, in Restatement Second section 402A,6 which in turn was rapidly adopted by most states in the United States and greatly influenced the adoption of product liability laws in other countries.7 However, as the courts attempted to apply strict liability as articulated in section 402A, renewed debate developed on the proper extent and grounds of product liability.8 By the time the Restatement Third was being drafted, it was generally agreed, at least among the courts, that liability for construction defects should be strict and that liability for warning defects should be based on negligence, while considerable disagreement remained about the proper grounds of liability for design defects.9 The Restatement Third continues to invoke all four of the rationales that Traynor set forth in Escola-and a few more-to support strict liability for construction defects, but it asserts that those rationales do not support strict liability for design or warning defects, which it claims "are predicated on a different concept of responsibility"10 and were not prominent in the cases or a subject of significant consideration at the time that Restatement Second section 402A was drafted and adopted.11 It is true that at the time that section 402A was adopted no clear distinction was drawn between construction defects and design or warning defects, but this is not because little consideration was given to design or warning defects, but rather because the prevailing academic and judicial view was that there was no need to distinguish the types of defect since it was assumed that strict liability should apply regardless of the type of defect. Greenman itself involved a design defect, which the court loosely described as a "defect in design and manufacture,"12 and section 402A clearly was meant to encompass design and warning defects as well as construction defects. Their inclusion was the reason for the insertion of the mischievous phrase "unreasonably dangerous" in section 402A. This phrase, along with repetitive language in comments h through k, was intended to preclude strict liability for generic product risks if, but only if, those risks were unavoidable aspects of a useful and reasonably safe product and proper warnings were provided.13 The Restatement Third's rote invocation of the efficiency rationales is unfortunate, not merely because they are normatively unappealing14 but also because they fail to explain or justify the differential treatment of construction defects and design and warning defects, or indeed any of the content or structure of past or current product liability law,15 which however can be explained and justified by Traynor's other rationales, which are based on interactive justice rather than efficiency.16 Except for its making the existence of a reasonable alternative design an independent requirement that the plaintiff must prove to establish a design defect, rather than only a factor to be considered in its consumer-oriented risk-utility analysis of reasonableness, the Restatement Third's substantive provisions and comments present a generally accurate description of current product liability law. …