Local Lodge No. 1424, International Association of MacHinists, Afl-Cio v. National Labor Relations Board

Summary

Justice Harlan's opinion held that § 10(b)'s six-month limitations period barred complaints attacking continued enforcement of a facially lawful union-security agreement when the alleged illegality depended entirely on the union's lack of majority status at execution outside the limitations period. Earlier events may illuminate independently unlawful conduct within the period, but cannot supply the indispensable unfair labor practice on which an otherwise lawful current act depends. The Court also rejected a presumption that enforcement of a union-security clause is unlawful. Justice Frankfurter dissented separately, agreeing with Justice Whittaker and arguing that active enforcement within the limitations period was actionable, much like overt acts continuing a conspiracy. Justice Whittaker, joined by Justice Frankfurter, would have affirmed because enforcement constituted a continuing violation, evidence of the agreement's original illegality remained admissible, and the General Counsel had established a prima facie case.