Litigation Newsletter
The Use of Circumstantial Evidence to Prove Product Defect
Individuals who have been injured by a defective product will have a valid legal claim against the manufacturer or distributor of the product if they can prove that the product was defective and that the product defect caused their injury. Traditionally, courts have required the injured party in a product liability case to prove their case with direct evidence, by testifying as to how the product injured them and having an expert testify that a defect in the product caused their injury. However, courts in some states have recognized that the injured party in a product liability case may sometimes use circumstantial evidence when they are unable to identify a specific defect in the product at issue.
The Circumstantial Evidence Standard
When injured parties in product liability cases are unable to identify a specific product defect through either their own testimony or expert testimony, some courts allow them to use circumstantial evidence. Specifically, if the sequence of circumstances leading up to their injury point to a product defect, some courts will assume that a defect must have existed and that the injury would not have otherwise occurred. In other words, some incidents are so out of the ordinary that courts will assume that the product must have been defective, even if the injured party cannot directly prove that a specific defect existed.
For example, consider a case where the injured party claims that a new television caused a fire. The fire destroyed the television, so the injured party is unable to identify a specific defect in the television. In states that only allow direct evidence to prove product defect, this injured party would not have a successful product liability claim. However, in states that allow the injured party to use circumstantial evidence to prove product defect, the injured party in this case could show that the television was new and had no problems prior to the fire; that the heaviest burn pattern occurred where the television was located; and that at least one witness is able to exclude all other possible causes of the fire other than the television.
New Products vs. Used Products
Initially, courts that accepted circumstantial evidence in product liability cases limited the admissibility of such evidence to cases where the products at issue were new. However, courts have gradually begun to allow the use of circumstantial evidence to prove defects in new and used products, as long as the product was in substantially the same condition at the time of injury as when it was delivered to the purchaser.
Still, not all courts recognize circumstantial evidence in product liability cases, and the requirements for use of circumstantial evidence in courts that do recognize it vary from state to state. Further, while courts that allow circumstantial evidence to prove a product defect do not always require expert testimony of the defect, there has been a strong preference in favor of expert testimony to eliminate all other possible causes of injury other than the alleged defect.
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