Lexis Nexis - Case Brief

Not a Lexis+ subscriber? Try it out for free.

Law School Case Brief

Potter v. Chi. Pneumatic Tool Co. - 241 Conn. 199, 694 A.2d 1319 (1997)


In order to recover under the doctrine of strict liability in tort, the plaintiff must prove that: (1) the defendant was engaged in the business of selling the product; (2) the product was in a defective condition unreasonably dangerous to the consumer or user; (3) the defect caused the injury for which compensation was sought; (4) the defect existed at the time of the sale; and (5) the product was expected to and did reach the consumer without substantial change in condition.

In order to prevail in a design defect claim, the plaintiff must prove that the product is unreasonably dangerous. The court's definition of "unreasonably dangerous" is that the article sold must be dangerous to an extent beyond that which would be contemplated by the ordinary consumer, who purchases it with the ordinary knowledge common to the community as to its characteristics. 

There may be instances involving complex product designs in which an ordinary consumer may not be able to form expectations of safety. In such cases, a consumer's expectations may be viewed in light of various factors that balance the utility of the product's design with the magnitude of its risks.

A jury's determination that a subsequent alteration or modification constituted the sole proximate cause of a plaintiff's harm is not the end of the inquiry. Conn. Gen. Stat. § 52-572p(a) provides that a manufacturer may still be strictly liable if the alteration or modification: (1) was in accordance with the manufacturer's instructions or specifications; (2) was made with the manufacturer's consent; or (3) was the result of conduct that the manufacturer reasonably should have anticipated. 

State of the art is a relevant factor in considering the adequacy of the design of a product and whether it is in a defective condition unreasonably dangerous to the ordinary consumer. The court defines "state of the art" as the level of relevant scientific, technological, and safety knowledge existing and reasonably feasible at the time of design.


John Potter and others were employed as grinders at Electric Boat. They used pneumatic hand tools manufactured by Chicago Pneumatic Tool Co. (Pneumatic Tool) to smooth welds and metal surfaces for 25 years. The prolonged usage resulted in permanent vascular and neurological impairment of their hands, which has caused blanching of their fingers, pain, numbness, tingling, reduction of grip strength, intolerance of cold and clumsiness from restricted blood flow. As a result, they were unable to continue their employment. Expert testimony confirmed that the syndrome was directly related to the level of vibration pressure of the pneumatic hand tool. Testimonies were presented to support the allegations that tools by Pneumatic Tool had higher vibration exposure than those prescribed by organizations. Also, that the company could have reduced such vibrations following published studies.

The trial court rendered judgment on jury verdicts in favor of Potter and the other grinders. It ruled that the tools were unreasonably dangerous because of the defective design. Further, Pneumatic Tool also provided inadequate warnings to prevent the injuries. Pneumatic Tool appealed, arguing that the grinders had the burden of presenting an alternative design to establish a prima facie case of design defect claim.


Were the grinders required to present an alternative design to establish a prima facie case of design defect claim against Pneumatic Tool?




The Court adopted a modified formulation of the consumer expectation test through the incorporation of risk-utility factors into the ordinary consumer expectation analysis. According to the appellate court, the grinders did not have the burden to prove that an alternative design is available; rather, this is only a factor considered to establish that a product’s risk outweigh its utility. The Court found that the testimonies presented proved that tools were defectively designed. The Court agreed with the trial court that to be absolved from liability, Pneumatic Tool had the burden of proving that any alterations made by other by third-party vendors is the proximate cause of the injuries. The Court ruled that the grinders had the burden of proving that they received the product without substantial change and that any alterations made were in line with the enumerations provided by the law.

The Court also ruled that the state-of-the-art evidence should not be limited to the grinders' failure to warn claims as such evidence is also relevant to determine whether the product design is unreasonably dangerous. State-of-the-art evidence, however, is not an affirmative defense to a design defect claim. Finally, the Court disagreed with the trial court’s exclusion of the grinders' evidence regarding the number of persons with similar symptoms as it was relevant in proving punitive damage claim. The trial court also abused its discretion when it admitted in evidence videotapes showing the Pneumatic Tool’s manufacturing process for being irrelevant. According to the Court, the products shown in the videotapes were manufactured later than the tools used by the grinders was not evidence presented that such process was substantially the same with the process used to manufacture the products subject of the litigation.

The Court reversed the judgment and remanded it for a new trial on the design defect claim and punitive damages claim in connection with the design defect claim.

Access the full text case Not a Lexis+ subscriber? Try it out for free.
Be Sure You're Prepared for Class