14 U.S. 304 (1816)
A dispute arose as to the preemption of Virginia statutes by federal treaties. In the subsequent decision, the Virginia Court of Appeals held that part of the Judiciary Act of 1789 was unconstitutional.
The Supreme Court reversed.
Justifying its authority to review the judicial opinions of states, the Court said that deference to the its decisions was a necessary check against the prejudices and biases of individual states, which might otherwise run rampant. Furthermore, the Court stressed the importance of its own function as the final arbiter in resolving differences in legal interpretation among the states.