1. THE PROBLEM Overlapping Jurisdiction #1 Cases involving federal law Exclusive jurisdiction Federal courts Concurrent jurisdiction 1331 “arising under” federal law State or federal courts Federal law issues claim not “arising under” state original jurisdiction only

2. THE PROBLEM Overlapping Jurisdiction #1 Cases involving federal law What law applies? U.S. Const., Art. VI (Supp. P. “Supremacy Clause”

3. THE PROBLEM Overlapping Jurisdiction #2 Cases arising under state law Concurrent jurisdiction Diversity cases What law applies? The “Erie Problem” 28 U.S.C. §1652 (Rules of Decision Act) The Constitution 28 U.S.C. §2071 (Rules Enabling Act)

4. THE PROBLEM Overlapping Jurisdiction #3 Cases arising under state law > 1 state has jurisdiction  > 1 federal court has jurisdiction What law applies? “Choice of law” rules Mostly judge-made common law U.S. Const., Art. IV “Full faith & credit” clause

5. READING STATUTES Rules of Decision Act 28 U.S.C. §1652, Supp. p. 334 The laws of the several states, except where the Constitution or Acts of Congress otherwise require or provide, shall be regarded as rules of decision in civil actions in courts of the United States, in cases where they apply.

6. READING STATUTES MAP-ing Rules of Decision Act Ambiguities?

7. READING STATUTES Ambiguities When we ask “what law applies” What counts as “law”?

8. READING STATUTES Ambiguities What do we mean by “rules of decision”?

9. HISTORICAL BACKGROUND Swift v. Tyson The “old” framework Cf. Pennoyer Under Swift v. Tyson What law applied in diversity cases? State statutes? State common law? i.e. judicial decisions

10. HISTORICAL BACKGROUND Swift v. Tyson Practical Implications?

11. ERIE RR. v. TOMPKINS Rule Choice Rule Choice D.Ct. & Ct. App.? S.Ct.?

12. ERIE RR. v. TOMPKINS Rationale Is Erie an obvious decision? Research problem Any PA laws on topic? What is “the law”?

13. ERIE RR. v. TOMPKINS Sources of Law Constitutional case What provisions of constitution? Candidates Equal protection 10 th Amendment No enumerated powers

14. TAKEAWAYS The Problem What law applies in diversity cases? Rules of Decision Act Where does law come from? Natural law Positivism

15. TAKEAWAYS Swift & Erie frameworks Swift (cf. Pennoyer) “Rules of decision” Includes statutes, not cases Erie (cf. Internat’l Shoe) “Rules of decision” Includes statutes + common law