Is state law Fed Rule on Point? Possibly/No Do BOTH
substantive / black NO (look at twin aims of Erie (Grey Area)
letter law? before deciding)
YES Byrd Test Hanna Dicta
Is state rule bound up with Analyze in light of twin
YES Hanna Holding (implementing of) state aims of Erie.
Apply Fed Rule if it’s valid created rights& 1. Forum Shopping?
obligations? Does it 2. Inequitable admin. of the
regulate primary behavior? laws?
State law applies
(f/ Erie & RDA)
Valid if reasonable person Y N Y N
would consider it procedural
State law Rule of form State law Fed law
Fed. Countervailing Outcome determinative
Interests (for fed law) test (for state law)
(always have uniformity, If outcome would be
but weak on its own. different depending on
Byrd was judge/jury which law applies (ie
relationship which statute of limitations is
outweighed outcome very determinative if its
determinency) run in state and not fed)