Federal courts sitting in diversity jurisdiction must apply the substantive law of the relevant state, overruling Swift v Tyson.
Choice of Law and Federalism
Chevron U.S.A. v NRDC overruled; courts must independently interpret statutes and may not defer to agency interpretations solely because of statutory ambiguity.
The Seventh Amendment right to jury trial applies to SEC administrative fraud proceedings seeking civil penalties, rendering ALJ adjudication of such claims unconstitutional.
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