Erie doctrine

The Erie doctrine is a fundamental legal doctrine of civil procedure in the United States which mandates that a federal court called upon to resolve a dispute not directly implicating a federal question (most commonly when sitting in diversity jurisdiction, but also when applying supplemental jurisdiction to claims factually related to a federal question or in an adversary proceeding in bankruptcy) must apply state substantive law.

Erie doctrine

The Erie doctrine is a fundamental legal doctrine of civil procedure in the United States which mandates that a federal court called upon to resolve a dispute not directly implicating a federal question (most commonly when sitting in diversity jurisdiction, but also when applying supplemental jurisdiction to claims factually related to a federal question or in an adversary proceeding in bankruptcy) must apply state substantive law.