Erieblogging: Day Ten

In honor of the 75th anniversary of Erie Railroad Co. v. Tompkins, I’m posting an un- or underexplored question about Erie each day for the whole month.

Today’s question: The scope of federal courts’ power to make federal common law is not an underexplored question. It is, if anything, overexplored. But assume that a federal court has the power to create federal common law. It nevertheless declines to do so, and applies state law instead. What are its Erie obligations when interpreting this law? Does it have any Erie obligations? Could one argue that even a gross misinterpretation of state law is constitutionally permissible, since it can simply be reconceptualized as the permissible creation of a federal common law rule? Such an argument, combined with an expansive theory of federal courts’ common lawmaking power would make Erie irrelevant.

For example, Erie concerned a railroad’s duty of care to a trespasser on a path running parallel to the railroad tracks. Given the connection between railroads and interstate commerce, this is arguably an area where a federal court has the power to create a federal common law rule. But according to the above argument, it would follow that the federal court in Erie had no constitutional duty to abide by the decisions of the Pennsylvania Supreme Court after all. Any misinterpretation of Pennsylvania law would simply be the creation of a federal common law rule.

(Note: This is parallel posted on my CivPro Blog.)