Arizona v. Inter Tribal Council of Arizona (2013)
Arizona required proof of citizenship to register using the federal voter form. The Supreme Court ruled 7-2 that federal law overrode the state's added requirement for federal elections.
Arizona could not reject federal-form registrations for lacking citizenship proof.
The case set a marker for how federal and state authority divide control over voter registration rules.
Both fights turn on the same question the current case raises: who sets the rules for registering and casting a ballot.
