In the case of Oregon v. Mitchell, decided in 1970, the U.S. Supreme Court addressed the legality of certain provisions of the Voting Rights Act of 1965. The case arose when the state of Oregon challenged the federal law that required states to allow 18-year-olds to vote in federal, state, and local elections. The Court ruled that while the federal government could set voting age requirements for federal elections, it could not impose those requirements on state and local elections. This decision highlighted the balance of power between state and federal authority in regulating voting rights.