Supreme Court rules in Printz v. United States that Congress can't commandeer local sheriffs to enforce federal gun law

The Supreme Court ruled 5-4 in Printz v. United States that Congress had violated the Tenth Amendment by requiring local law enforcement officers to conduct background checks under the Brady Handgun Violence Prevention Act. Justice Antonin Scalia wrote for the majority that directing state and local officials to carry out federal law was "fundamentally incompatible with our constitutional system of dual sovereignty." Sheriffs Jay Printz of Montana and Richard Mack of Arizona had challenged the Brady Bill's interim mandate requiring them to perform checks until a federal system was ready. The ruling built on New York v. United States (1992) and established the anti-commandeering doctrine as a firm constitutional limit on federal power over state and local officials.