|OPINION BY: POLLOCK
Plaintiff, Gary O'Brien, seeks to recover in strict liability for personal injuries sustained because defendant, Muskin Corporation, allegedly marketed a product, an above-ground swimming pool, that was defectively designed and bore an inadequate warning. In an unreported decision, the Appellate Division reversed the judgment for defendants and remanded the matter for trial. We granted certification, . . . and now modify and affirm the judgment of the Appellate Division. In reaching that result, we conclude that state-of-the-art evidence is relevant to risk-utility analysis and admissible in a strict liability case involving a defectively designed product.
O'Brien sued to recover damages for serious personal injuries sustained when he dove into a swimming pool at the home of Jean Henry, widow of Arthur Henry, now Jean Glass. Ultimately, plaintiff sued as defendants not only Muskin Corporation, the manufacturer, but also Kiddie City Inc., the distributor of the pool, charging them with placing a defectively designed pool in the stream of commerce. Kiddie City filed a third-party complaint for contribution against the owners of the pool. Defendants filed cross-claims for contribution and indemnification against each other, and Muskin filed a cross-claim against the owners.
At the beginning of the jury trial, the claims against Kiddie City were dismissed with the consent of the parties.
Muskin, a swimming pool manufacturer, made and distributed a line of above-ground pools. Typically, the pools consisted of a corrugated metal wall, which the purchaser placed into an oval frame assembled over a shallow bed of sand. This outer structure was then fitted with an embossed vinyl liner and filled with water.
In 1971, Arthur Henry bought a Muskin pool and assembled it in his backyard. The pool was a twenty-foot by twenty-four-foot model, with four-foot walls. An embossed vinyl liner fit within the outer structure and was filled with water to a depth of approximately three and one-half feet. At one point, the outer wall of the pool bore the logo of the manufacturer, and below it a decal that warned "DO NOT DIVE" in letters roughly one-half inch high.
On May 17, 1974, O'Brien, then twenty-three years old, arrived uninvited at the Henry home and dove into the pool. A fact issue exists whether O'Brien dove from the platform by the pool or from the roof of the adjacent eight-foot high garage. As his outstretched hands hit the vinyl-lined pool bottom, they slid apart, and O'Brien struck his head on the bottom of the pool, thereby sustaining his injuries.
In his complaint, O'Brien alleged that Muskin was strictly liable for his injuries because it had manufactured and marketed a defectively designed pool. In support of this contention, O'Brien cited the slippery quality of the pool liner and the lack of adequate warnings.
At trial, both parties produced experts who testified about the use of vinyl as a pool liner. One of the plaintiff's witnesses, an expert in the characteristics of vinyl, testified that wet vinyl was more than twice as slippery as rubber latex, which is used to line in-ground pools. The trial court, however, sustained an objection to the expert's opinion about alternative kinds of pool bottoms, specifically whether rubber latex was a feasible liner for above-ground pools. The expert admitted that he knew of no above-ground pool lined with a material other than vinyl, but plaintiff contended that vinyl should not be used in above-ground pools, even though no alternative material was available. A second expert testified that the slippery vinyl bottom and lack of adequate warnings rendered the pool unfit and unsafe for its foreseeable uses.
Muskin's expert testified that vinyl was not only an appropriate material to line an above-ground pool, but was the best material because it permitted the outstretched arms of the diver to glide when they hit the liner, thereby preventing the diver's head from striking the bottom of the pool. Thus, he concluded that in some situations, specifically those in which a diver executes a shallow dive, slipperiness operates as a safety feature. Another witness, Muskin's customer service manager, who was indirectly in charge of quality control, testified that the vinyl bottom could have been thicker and the embossing deeper. A fair inference could be drawn that deeper embossing would have rendered the pool bottom less slippery.
At the close of the entire case, the trial court instructed the jury on the elements of strict liability, both with respect to design defects and the failure to warn adequately. The court, however, then limited the jury's consideration to the adequacy of the warning. That is, the court took from the jury the issue whether manufacturing a pool with a vinyl liner constituted either a design or manufacturing defect.
Strict liability law, a relatively recent but rapidly growing legal phenomenon, has received uneven treatment from scholars, legislatures and courts. Underlying the various responses is a shared concern about the allocation of the risk of loss upon manufacturers, distributors and others in the stream of commerce for injuries sustained by the public from unsafe products.
One of the policy considerations supporting the imposition of strict liability is easing the burden of proof for a plaintiff injured by a defective product, a policy that is achieved by eliminating the requirement that the plaintiff prove the manufacturer's negligence. . . . Generally speaking, a plaintiff has the burden of proving that (1) the product was defective; (2) the defect existed when the product left the hands of the defendant; and (3) the defect caused injury to a reasonably foreseeable user. . . . Proof that the product was defective requires more than a mere showing that the product caused the injury. The necessity of proving a defect in the product as part of the plaintiff's prima facie case distinguishes strict from absolute liability, and thus prevents the manufacturer from also becoming the insurer of a product. . . .
Fundamental to the determination of a products liability case, including one predicated on a defective design or inadequate warning, is the duty of the manufacturer to foreseeable users. The duty includes warning foreseeable users of the risks inherent in the use of that product, . . . and not placing defective products on the market. . . . A manufacturer who breaches these duties is strictly liable to an injured party. That liability reflects the policy judgment that by marketing its product, a manufacturer assumes responsibility to members of the public who are injured because of defects in that product. . . .
In determining whether a manufacturer has breached its duty, we focus on the product. . . . Under strict liability, a manufacturer that produces defective products is liable even if those products are carefully produced. Thus, the legal standard for evaluating whether a product is defective becomes the touchstone of strict liability.
Critical, then, to the disposition of products liability claims is the meaning of "defect". The term is not self-defining and has no accepted meaning suitable for all strict liability cases. Implicit in the term "defect" is a comparison of the product with a standard of evaluation; something can be defective only if it fails to measure up to that standard. . . . Speaking generally, defects may be classified as design defects or manufacturing defects. In cases alleging manufacturing defects, as distinguished from design defects, defining the standard, and thus the meaning of "defect," is relatively easy. For example, the injury-causing product may be measured against the same product as manufactured according to the manufacturer's standards. If the particular product used by the plaintiff fails to conform to those standards or other units of the same kind, it is defective. An apt illustration is a mass-produced product that comes off the assembly line missing a part. The question in those cases becomes whether the product as produced by the manufacturer conformed to the product as intended. . . .
The considerations are more subtle when a plaintiff alleges that a product is defective due to any feature of its design, including the absence or inadequacy of accompanying warnings. In design defect or failure-to-warn cases, the product has been manufactured as intended and cannot be "defective" by comparison to a standard set by the manufacturer. . . . Rather, the standard to measure the product reflects a policy judgment that some products are so dangerous that they create a risk of harm outweighing their usefulness. From that perspective, the term "defect" is a conclusion rather than a test for reaching that conclusion. . . .
Although the appropriate standard might be variously defined, one definition, based on a comparison of the utility of the product with the risk of injury that it poses to the public, has gained prominence. To the extent that "risk-utility analysis," as it is known, implicates the reasonableness of the manufacturer's conduct, strict liability law continues to manifest that part of its heritage attributable to the law of negligence. . . . Risk-utility analysis is appropriate when the product may function satisfactorily under one set of circumstances, yet because of its design present undue risk of injury to the user in another situation.
Another standard is the consumer expectations test, which recognizes that the failure of the product to perform safely may be viewed as a violation of the reasonable expectations of the consumer. . . . In this case, however, the pool fulfilled its function as a place to swim. The alleged defect manifested itself when the pool was used for diving.
. . . [S]ome factors relevant in risk-utility analysis are:
(1) The usefulness and desirability of the product -- its utility to the user and to the public as a whole.
(2) The safety aspects of the product -- the likelihood that it will cause injury, and the probable seriousness of the injury.
(3) The availability of a substitute product which would meet the same need and not be as unsafe.
(4) The manufacturer's ability to eliminate the unsafe character of the product without impairing its usefulness or making it too expensive to maintain its utility.
(5) The user's ability to avoid danger by the exercise of care in the use of the product.
(6) The user's anticipated awareness of the dangers inherent in the product and their avoidability, because of general public knowledge of the obvious condition of the product, or of the existence of suitable warnings or instructions.
(7) The feasibility, on the part of the manufacturer, of spreading the loss by setting the price of the product or carrying liability insurance. . . .
By implication, risk-utility analysis include other factors such as the "state-of-the-art" at the time of the manufacture of the product. . . . The "state-of-the-art" refers to the existing level of technological expertise and scientific knowledge relevant to a particular industry at the time a product is designed. . . . Although customs of an industry may be relevant, . . . because those customs may lag behind technological development, they are not identical with the state-of-the-art. . . . A manufacturer may have a duty to make products pursuant to a safer design even if the custom of the industry is not to use that alternative.
Although state-of-the-art evidence may be dispositive on the facts of a particular case, it does not constitute an absolute defense apart from risk-utility analysis. . . . The ultimate burden of proving a defect is on the plaintiff, but the burden is on the defendant to prove that compliance with state-of-the-art, in conjunction with other relevant evidence, justifies placing a product on the market. Compliance with proof of state-of-the-art need not, as a matter of law, compel a judgment for a defendant. State-of-the-art evidence, together with other evidence relevant to risk-utility analysis, however, may support a judgment for a defendant. In brief, state-of-the-art evidence is relevant to, but not necessarily dispositive of, risk-utility analysis. That is, a product may embody the state-of-the-art and still fail to satisfy the risk-utility equation.
The assessment of the utility of a design involves the consideration of available alternatives. If no alternatives are available, recourse to a unique design is more defensible. The existence of a safer and equally efficacious design, however, diminishes the justification for using a challenged design.
The evaluation of the utility of a product also involves the relative need for that product; some products are essentials, while others are luxuries. A product that fills a critical need and can be designed in only one way should be viewed differently from a luxury item. Still other products, including some for which no alternative exists, are so dangerous and of such little use that under the risk-utility analysis, a manufacturer would bear the cost of liability of harm to others. That cost might dissuade a manufacturer from placing the product on the market, even if the product has been made as safely as possible. Indeed, plaintiff contends that above-ground pools with vinyl liners are such products and that manufacturers who market those pools should bear the cost of injuries they cause to foreseeable users.
A critical issue at trial was whether the design of the pool, calling for a vinyl bottom in a pool four feet deep, was defective. The trial court should have permitted the jury to consider whether, because of the dimensions of the pool and slipperiness of the bottom, the risks of injury so outweighed the utility of the product as to constitute a defect. In removing that issue from consideration by the jury, the trial court erred. To establish sufficient proof to compel submission of the issue to the jury for appropriate fact-finding under risk-utility analysis, it was not necessary for plaintiff to prove the existence of alternative, safer designs. Viewing the evidence in the light most favorable to plaintiff, even if there are no alternative methods of making bottoms for above-ground pools, the jury might have found that the risk posed by the pool outweighed its utility.
In a design-defect case, the plaintiff bears the burden of both going forward with the evidence and of persuasion that the product contained a defect. To establish a prima facie case, the plaintiff should adduce sufficient evidence on the risk-utility factors to establish a defect. With respect to above-ground swimming pools, for example, the plaintiff might seek to establish that pools are marketed primarily for recreational, not therapeutic purposes; that because of their design, including their configuration, inadequate warnings, and the use of vinyl liners, injury is likely; that, without impairing the usefulness of the pool or pricing it out of the market, warnings against diving could be made more prominent and a liner less dangerous. It may not be necessary for the plaintiff to introduce evidence on all those alternatives. Conversely, the plaintiff may wish to offer proof on other matters relevant to the risk-utility analysis. It is not a foregone conclusion that plaintiff ultimately will prevail on a risk-utility analysis, but he should have an opportunity to prove his case.
We modify and affirm the judgment of the Appellate Division reversing and remanding the matter for a new trial.