Machinists preemption

Labor law. The doctrine prohibiting state regulation of an area of labor activity or management–union relations that Congress has intentionally left unregulated. Lodge 76, Int’l Ass’n of Machinists v. Wisconsin Employment Relations Comm’n, 427 U.S. 132, 96 S.Ct. 2548 (1976). [Cases: Labor Relations 45. C.J.S. Labor Relations § 23.]