1. “Does constitutional federalism require a federal court that confronts an outcome-determinative and unresolved State law issue that is particularly within the expertise of a State court—here, whether railroad deeds created an easement or fee simple title, a question antecedent to Petitioners’ Fifth Amendment takings claim—to certify the question of State law to the State’s highest court rather than making an Erie-guess about how the State’s highest court would decide the issue?”
2. “Under what standards may a federal court make an Erie-guess about how the State’s highest court would decide an outcome-determinative issue?”
