On the tenth anniversary of the Restatement (Third) of Torts: Products Liability,1 it is fitting to observe from whence the law of products liability has come and to look a bit at where it presently resides. Truly modern products liability law in the United States2 is fairly viewed as being about half a century old, beginning with the rise of strict liability for manufacturers of defective products in the late 1950s and early 1960s. In fact, however, much of the story of products liability law begins much longer ago than that. Important aspects of the modern law of products liability rest on principles of strict seller liability for defective goods rooted in custom and law as far back as the eye can see, at least to Roman law, which imposed an implied warranty of quality against defects on sellers of certain goods,3 a rule that may be traced to ancient Babylon, one or two thousand years before.4
More recently, elemental foundations of modern products liability law lie in the early law of England and America, and it suffices here to begin our evolutionary inquiry with a consideration of those vital tap roots of our modern law. Modern products liability policy and doctrine, originating in warranty and tort, draws from a deep reservoir of recent academic thought.5 As important as this foundational scholarship may be, the flowering of modern law in this field evolved essentially from the intertwining of two conceptual roots: the ancient idea that sellers should be strictly responsible for defects in goods they sell together with the largely modern idea that a person injured by a defective product may hold the manufacturer accountable although no contract of sale existed between the two. It was the union of these two important legal concepts-strict liability (drawn from the contract of sale) and the irrelevance of privity of contract (drawn from the law of tort)-that spawned the brightest blossom of modern products liability doctrine, strict manufacturer liability in tort.
Yet, while the explosive rise of the doctrine of strict liability for manufacturers of defective products during the 1960s and 1970s is the most striking development in modern products liability law, the law did not settle there, at least not in how most product liability cases are evaluated in the United States. While European and, more slowly, other nations are just beginning to work through the meaning of "strict" manufacturer liability in various contexts,6 a heavy preponderance of American jurisdictions, as reflected and guided by the Third Restatement, have returned the bulk of modern manufacturer liability law to its more natural home in fault. And, despite some protests here and there, this is where the modern law of products liability presently, and comfortably, resides.
II. EARLY ENGLISH LAW
In early medieval English law, the law governing a seller's responsibility for defects in its products was crude at best.7 Indeed, private law, under which an aggrieved buyer might sue the seller for damages caused by defective goods, was largely unknown in early England.8 In time, guilds of the various crafts developed an elaborate system of localized criminal regulation of product quality by statutes that often developed into ordinances of the town. But such local statutes were designed to protect the public more from being cheated than from being injured. The late Roman law's insistence on the fair quality of goods sold was largely absent from the rustic local law of medieval England, but certain aspects of Justinian's Digest from late Roman law wended their way to a limited extent into early English law through the dominant role in society of the church, the scholars of which were trained in the civil law.9
In the thirteenth century, Thomas Aquinas (1225?-1274 A.D.) in his Summa Theologica10 outlined the basic mercantile obligations consistent with those expressed by Justinian in his Digest.11 Thus, the seller was bound to disclose secret flaws: it was sin and fraud to sell a product containing a latent defect known to the seller and not the buyer, and the sale was void. …