Erie Railroad Co. v. Tompkins, 304 U.S. 64 (1938)
Erie Railroad Co. v.
Should federal courts apply state law or federal general common law when deciding claims under diversity jurisdiction?
Federal courts must apply state law—the statutory and common law—of the states where they sit when adjudicating cases based on diversity jurisdiction.
The Supreme Court held that federal courts must apply state law in diversity jurisdiction cases, effectively overruling the doctrine established in Swift v. Tyson.
Erie Railroad Co. v. Tompkins is pivotal for law students as it illustrates a fundamental shift in the relationship between federal and state law. The decision underscores the principle that state law governs substantive rights for federal diversity cases, reinforcing the importance of state sovereignty in shaping their own judicial destinies. This case serves as a critical touchstone in understanding the limits of federal judicial power and the application of state laws within the federal system. Its legacy continues to influence the study and practice of law, particularly in the realm of civil procedure.