One of the legacies of the Restatement of Torts, Second, Section 402A published in 1965, is the so-called “heeding presumption.” Section 402A’s Comment j afforded product sellers a presumption that an adequate warning, when given, would be heeded to avoid the risk: “Where a warning is given, the seller may reasonably assume that it will be read and heeded.” However, courts soon began inverting Comment j to create a presumption favoring plaintiffs; i.e., that since they would have heeded an adequate warning, they need not show that the absence of an “adequate” warning caused their injury. Effectively, the heeding presumption shifts the burden to the seller to disprove causation.

In 1998 the American Law Institute issued the Restatement (Third) of Torts, Product Liability, Section 2, which contains no such presumption, saying that “it has elicited heavy criticism from a host of commentators.”[1] State law is divided on whether a heeding presumption exists, and if so, its effect. But since many products are sold and distributed nationally, sellers must anticipate being sued almost anywhere, and accordingly, must heed the law in the most plaintiff-friendly states. Among those is Missouri.

Missouri adopted the heeding presumption in the 1980s, and the Missouri Supreme Court has repeatedly re-affirmed it. In Moore v. Ford Motor Company, a 300 pound plaintiff injured when her seat collapsed in a rear-end collision sued on design defect and failure to warn claims.[2] Plaintiff contended that Ford failed to warn that its seat could collapse in a rear end collision involving such an overweight occupant. Ford argued that plaintiff’s experts offered no evidence that the Explorer was defective and unreasonably dangerous without such a warning, and that the jury verdict for Ford on design defect precluded recovery on failure to warn as well. The trial court directed a verdict for Ford on the warning claim, and the jury returned a defense verdict on design defect. The Missouri Supreme Court reversed. Pointing to the difference between design defect and failure to warn, it said, “lack of an adequate warning in itself renders a product defective or reasonably dangerous within the meaning of the law,” while declining to require plaintiffs to show what they claimed would constitute an “adequate” warning.

As to causation, the Court held that evidence of what a person “would have done” had a warning been given is inherently hypothetical. This, it said, creates a “Catch-22” because the plaintiff must prove what she would have done had a warning been given to prove causation, but evidence on this issue must be precluded as speculative.” According to the Court, the heeding presumption avoids this dilemma.

Although Missouri recognizes strict liability failure to warn—i.e., a product seller can be held liable for failing to warn about a hazard unknown to it—the Moore plaintiffs claimed they had a submissible case of negligent failure to warn. The Court agreed. It held that Ford was negligent, based on plaintiff’s expert testimony that the seat was negligently designed because it was incapable of protecting a 300 pound occupant from injury in a rear end crash, but Ford failed to warn about this—obliterating the distinction between design defect and failure to warn. And it further confused the issues by saying, “the causation elements are the same for both strict liability and negligent failure to warn.”

In states like Missouri, the combination of strict liability failure to warn and the heeding presumption makes almost any product related injury actionable, and product sellers are virtually their customers’ insurers. Faced with this, how should a prudent seller proceed? Here are some suggestions.

Consult human factors experts, rather than relying on lay intuition, in creating product warnings. Establish written procedures for identifying and addressing the hazards associated with products, incorporating applicable regulatory requirements and industry standards (e.g., ANSI Z535 and ISO 3864). Develop a master template for instructions, directions, advertising and marketing materials, as well as warnings, to avoid discrepancies and inconsistency. And create a non-privileged record of how these elements are used in devising warnings. These steps provide a basis for defending warning claims by showing that the seller cares about users and does its best to protect them. There are few safe harbors in warnings law, but sellers should can, and should, put their best foot forward.