Erie Railroad Co. v. Tompkins

Tompkins (plaintiff), a Pennsylvania citizen injured walking along railroad tracks owned by Erie Railroad (defendant), a New York company, sued in New York federal court; under the old Swift v. Tyson rule, the trial court applied general federal common law rather than Pennsylvania's stricter trespasser liability standard, resulting in judgment for Tompkins under the more favorable ordinary-care standard that federal courts had developed independently of state law.