What is the Erie Doctrine in regards to federal courts?

The Erie Doctrine is a fundamental principle in U.S. federal court system, particularly regarding how federal courts handle cases based on diversity jurisdiction. The doctrine stems from the Supreme Court case Erie Railroad Co. v. Tompkins, which established that in diversity cases, federal courts must apply state substantive law rather than federal law.

Option B is correct because it addresses a crucial aspect of the Erie Doctrine: when a federal court is deciding a case under diversity jurisdiction, it will apply the relevant state law if that law pertains to the elements necessary to establish the claims and defenses in the case, which often includes creating substantive rights. This ensures that the outcome of a case does not unfairly favor one party over another simply based on the choice of forum, thereby promoting fairness and uniformity within the legal system.

The other options do not align with the Erie Doctrine. The notion that federal courts only apply federal law in all cases ignores the essential requirement to apply state law in certain situations, especially in diversity cases. Suggesting that federal courts cannot hear diversity cases misinterprets the doctrine's intent and establishes a misleading premise. Finally, characterizing state and federal law as treated equally fails to capture the specific guidance provided by the Erie Doctrine on the application of state