To this point, we have considered principles of liability that in some sense depend upon the “fault” of the tortfeasor. This fault is not synonymous with moral blame.
Aside from acts intended to harm, the fault lies in a failure to live up to a standard of reasonableness or due care. But this is not the only basis for tort liability. Innocent mistakes can be a sufficient basis. As we have already seen, someone who unknowingly trespasses on another’s property is liable for the damage that he does, even if he has a reasonable belief that the land is his. And it has long been held that someone who engages in ultrahazardous (or sometimes, abnormally dangerous) activities is liable for damage that he causes, even though he has taken every possible precaution to avoid harm to someone else.
Likewise, the owner of animals that escape from their pastures or homes and damage neighboring property may be liable, even if the reason for their escape was beyond the power of the owner to stop (e.g., a fire started by lightning that burns open a barn door). In such cases, the courts invoke the principle of strict liability, or, as it is sometimes called, liability without fault. The reason for the rule is explained in Klein v. Pyrodyne Corporation (Section 7.5 "Cases").
Because of the importance of products liability, this text devotes an entire chapter to it (Chapter 20 "Products Liability"). Strict liability may also apply as a legal standard for products, even those that are not ultrahazardous. In some national legal systems, strict liability is not available as a cause of action to plaintiffs seeking to recover a judgment of products liability against a manufacturer, wholesaler, distributor, or retailer. (Some states limit liability to the manufacturer.) But it is available in the United States and initially was created by a California Supreme Court decision in the 1962 case of Greenman v. Yuba Power Products, Inc.
In Greenman, the plaintiff had used a home power saw and bench, the Shopsmith, designed and manufactured by the defendant. He was experienced in using power tools and was injured while using the approved lathe attachment to the Shopsmith to fashion a wooden chalice. The case was decided on the premise that Greenman had done nothing wrong in using the machine but that the machine had a defect that was “latent” (not easily discoverable by the consumer). Rather than decide the case based on warranties, or requiring that Greenman prove how the defendant had been negligent, Justice Traynor found for the plaintiff based on the overall social utility of strict liability in cases of defective products. According to his decision, the purpose of such liability is to ensure that the “cost of injuries resulting from defective products is borne by the manufacturers…rather than by the injured persons who are powerless to protect themselves.”
Today, the majority of US states recognize strict liability for defective products, although some states limit strict liability actions to damages for personal injuries rather than property damage. Injured plaintiffs have to prove the product caused the harm but do not have to prove exactly how the manufacturer was careless. Purchasers of the product, as well as injured guests, bystanders, and others with no direct relationship with the product, may sue for damages caused by the product.
The Restatement of the Law of Torts, Section 402(a), was originally issued in 1964. It is a widely accepted statement of the liabilities of sellers of goods for defective products. The Restatement specifies six requirements, all of which must be met for a plaintiff to recover using strict liability for a product that the plaintiff claims is defective:
Section 402(a) also explicitly makes clear that a defendant can be held liable even though the defendant has exercised “all possible care.” Thus in a strict liability case, the plaintiff does not need to show “fault” (or negligence).
For defendants, who can include manufacturers, distributors, processors, assemblers, packagers, bottlers, retailers, and wholesalers, there are a number of defenses that are available, including assumption of risk, product misuse and comparative negligence, commonly known dangers, and the knowledgeable-user defense. We have already seen assumption of risk and comparative negligence in terms of negligence actions; the application of these is similar in products-liability actions.
Under product misuse, a plaintiff who uses a product in an unexpected and unusual way will not recover for injuries caused by such misuse. For example, suppose that someone uses a rotary lawn mower to trim a hedge and that after twenty minutes of such use loses control because of its weight and suffers serious cuts to his abdomen after dropping it. Here, there would be a defense of product misuse, as well as contributory negligence. Consider the urban (or Internet) legend of Mervin Gratz, who supposedly put his Winnebago on autopilot to go back and make coffee in the kitchen, then recovered millions after his Winnebago turned over and he suffered serious injuries. There are multiple defenses to this alleged action; these would include the defenses of contributory negligence, comparative negligence, and product misuse. (There was never any such case, and certainly no such recovery; it is not known who started this legend, or why.)
Another defense against strict liability as a cause of action is the knowledgeable user defense. If the parents of obese teenagers bring a lawsuit against McDonald’s, claiming that its fast-food products are defective and that McDonald’s should have warned customers of the adverse health effects of eating its products, a defense based on the knowledgeable user is available. In one case, the court found that the high levels of cholesterol, fat, salt, and sugar in McDonald’s food is well known to users. The court stated, “If consumers know (or reasonably should know) the potential ill health effects of eating at McDonald’s, they cannot blame McDonald’s if they, nonetheless, choose to satiate their appetite with a surfeit of supersized McDonald’s products.”Pellman v. McDonald’s Corp., 237 F.2d 512 (S.D.N.Y. 2003).
Common-law courts have long held that certain activities are inherently dangerous and that those who cause damage to others by engaging in those activities will be held strictly liable. More recently, courts in the United States have applied strict liability to defective products. Strict liability, however, is not absolute liability, as there are many defenses available to defendants in lawsuits based on strict liability, such as comparative negligence and product abuse.