(a) A plaintiff's recovery of damages for harm caused by a product defect may be reduced if the conduct of the plaintiff combines with the product defect to cause the harm and the plaintiff's conduct fails to conform to generally applicable rules establishing appropriate standards of care.

     (b) The manner and extent of the reduction under Subsection (a) and the apportionment of plaintiff's recovery among multiple defendants are governed by generally applicable rules apportioning responsibility.

a. History. The rule stated in this Section recognizes that the fault of the plaintiff is relevant in assessing liability for product-caused harm. Section 402A of the Restatement, Second, of Torts, recognizing strict liability for harm caused by defective products, was adopted in 1964 when the overwhelming majority rule treated contributory negligence as a total bar to recovery. Understandably, the Institute was reluctant to bar a plaintiff's products liability claim in tort based on conduct that was not egregious. Thus, § 402A, Comment n, altered the general tort defenses by narrowing the applicability of contributory negligence and emphasizing assumption of risk as the primary defense. Since then, comparative fault has swept the country. Only a tiny minority of states retain contributory fault as a total bar.

A strong majority of jurisdictions apply the comparative responsibility doctrine to products liability actions. Courts today do not limit the relevance of plaintiff's fault as did the Restatement, Second, of Torts to conduct characterized as voluntary assumption of the risk. See Comment d.

Certain forms of consumer behavior—product misuse and product alteration or modification—have been the subject of much confusion and misunderstanding. Early decisions treated product misuse, alteration, and modification, whether by the plaintiff or a third party, as a total bar to recovery against a product seller. Today misuse, alteration, and modification relate to one of three issues in a products liability action. In some cases, misuse, alteration, and modification are important in determining whether the product is defective. In others, they are relevant to the issue of legal cause. Finally, when the plaintiff misuses, alters, or modifies the product, such conduct may constitute contributory fault and reduce the plaintiff's recovery under the rules of comparative responsibility. See Comment c.

b. Conduct of the plaintiff. The applicable rules of apportionment of responsibility vary among jurisdictions. Some states have adopted “pure” comparative fault, which allocates responsibility to each actor purely in proportion to the actor's percentage of total fault. Others follow some variant of “modified” comparative fault, in which actors' responsibilities are adjusted according to predetermined thresholds of responsibility. For example, in many modified jurisdictions the plaintiff is totally barred if found more than 50 percent at fault. The apportionment of responsibility principles as they have developed in each jurisdiction should be applied to products liability cases. With respect to whether special exceptions should be made in products liability cases for certain categories of plaintiff conduct, see Comment d.

Illustration:

1. Roger was driving his car, manufactured by the ABC Motor Co., when he noticed the temperature light flashing. The instruction manual warned drivers that when the temperature light flashes it is a sign that the car is seriously overheating and that the car should be brought to a stop and the motor shut off. The overheating in this instance was caused by a hose, leaking coolant, that was defective at the time of sale by ABC. Roger had not read the instruction manual and paid no attention to the flashing temperature light. He continued driving for 30 minutes. The overheating of the car was so intense that it started an electrical fire in the car causing Roger serious harm. Roger's conduct in failing to read the manual and failing to pay attention to the flashing temperature light may be considered by the trier of fact to be negligent conduct warranting a reduction of Roger's recovery against ABC based on the percentage of fault attributed to him.

c. Misuse, alteration, and modification. Product misuse, alteration, and modification, whether by a third party or the plaintiff, are not discrete doctrines within products liability law. Instead such conduct is relevant to the determination of the issues of defect, causation, and comparative responsibility. See § 2, Comment p.

Jurisdictions differ on the question of who bears the burden of proof regarding conduct that constitutes misuse, modification, and alteration. The allocation of burdens in this regard is not addressed in this Restatement and is left to local law.

Illustration:

2. ABC Machine Tools, Inc. manufactures and sells pelletizer machines, which draw strands of plastic into position to be cut into very small pellets. The pelletizer comes equipped with a removable guard. It is necessary periodically to remove the      guard so that the inside of the machine can be cleaned. Fred, an employee of a plastics company, removed the guard on an ABC pelletizer to perform the cleaning but neglected to reinstall it. Fred resumed operation of the machine guard. Shortly thereafter a strand of plastic caught his hand and pulled it into the rollers of the machine, causing harm. Fred alleges that the pelletizer should have been equipped with an interlock mechanism that would have prevented the machine from operating without the safety guard in place. A trier of fact may conclude that the pelletizer was defectively designed and also that Fred's failure to replace the safety guard was a foreseeable alteration of the machine. The trier of fact may further find that Fred's conduct in failing to reinstall the safety guard and operating the machine without the guard constitutes negligent conduct on his part that should reduce his recovery proportionate to his fault.

d. Particular forms or categories of plaintiff's conduct. Some courts accord different treatment to special categories of plaintiff conduct. For example, some decisions hold that when the plaintiff's negligence is the failure to discover a product defect, reduction of damages on the basis of apportionment of responsibility is improper, reasoning that a consumer has a right to expect a defect-free product and should not be burdened with a duty to inspect for defects. Other decisions hold that apportionment of responsibility is improper when the product lacked a safety feature that would protect against the risk that resulted in the injury in question, reasoning that the defendant's responsibility should not be diminished when the plaintiff engages in the very conduct that the product design should have prevented. On the other hand, some decisions hold that a plaintiff's assumption of the risk is a complete defense to a products liability action, not merely a basis for apportionment of responsibility. Product misuse, alteration, and modification have been treated by some courts as an absolute bar to recovery and by others as a form of plaintiff fault that should be compared with that of other parties to reduce recovery. The majority position is that all forms of plaintiff's failure to conform to applicable standards of care are to be considered for the purpose of apportioning responsibility between the plaintiff and the product seller or distributor.

Before the court will allow any apportionment of responsibility, the defendant must introduce sufficient evidence to support a finding of fault on the part of the plaintiff. Thus, for example, when the defendant claims that the plaintiff failed to discover a defect, there must be evidence that the plaintiff's conduct in failing to discover a defect did, in fact, fail to meet a standard of reasonable care. In general, a plaintiff has no reason to expect that a new product contains a defect and would have little reason to be on guard to discover it. Or when a plaintiff is injured due to inattention to a danger that should have been eliminated by a safety feature, there must be evidence supporting the conclusion that the plaintiff's momentary inattention or inadvertence in a workplace setting constitutes failure to exercise reasonable care. In the absence of such evidence courts refuse to submit the plaintiff's conduct to the trier of fact for apportionment based on the principles of comparative responsibility. When evidence of plaintiff fault is established, how much responsibility to attribute to a plaintiff will vary with the circumstances. The seriousness of the plaintiff's fault and the nature of the product defect are relevant in apportioning the appropriate percentages of responsibility between the plaintiff and the product seller.