The advent of the new year seems an appropriate time to revisit the hot-button issue of “manifestation” in product defect cases. In some cases, a defective product fails to perform as intended from day one. In others, the defect remains latent, unknown to the consumer, until it “manifests,” sometimes resulting in severe physical injury. No matter whether the defect is latent or not, one expects that reasonable consumers would not be willing to pay the same price for a defective product compared to a non-defective product. As I have argued previously in this space, this economic injury should, at the very least, establish Article III standing in federal court. Significantly, the weight of recent authority on this point is in accord. See, e.g., Riddell v. General Motors LLC, 2024 WL 2077559 (E.D. Mo. May 9, 2024) (holding that Article III standing was satisfied for each class member given evidence of a class-wide vehicle defect).

Even after clearing Article III’s constitutional hurdle, however, class plaintiffs alleging a product defect frequently face the same kinds of manifestation arguments under state law. Thus, federal courts are placed in the unenviable position of determining, under Erie, whether the product defect claims of each state at issue—up to all 50 in the most sprawling multidistrict litigations—include a requirement that the defect manifest in some fashion. The differences among the states’ laws in this area should be minimal: breach of warranty claims generally arise under the same Uniform Commercial Code provisions, fraud claims all stem from the same source in common law, and the states’ respective consumer protection statutes are mainly based on a relatively small number of pattern statutes addressing unfair and deceptive trade practices. Nevertheless, courts typically tackle the manifestation question on a state-by-state basis.