The Norris–La Guardia Act (also known as the Anti-Injunction Bill) is a 1932 United States federal law on US labor law. It banned yellow-dog contracts, barred the federal courts from issuing injunctions against nonviolent labor disputes, and created a positive right of noninterference by employers against workers joining trade unions. The common title comes from the names of the sponsors of the legislation: Senator George W. Norris of Nebraska and Representative Fiorello H. La Guardia of New York, both Republicans.
In the 1917 United States Supreme Court case Hitchman Coal & Coke Co. v. Mitchell, the court established the Hitchman doctrine, which held that yellow-dog contracts were enforceable. In the aftermath of that case, the number of judicial injunctions against labor increased substantially, and organizing a union without the employer's consent became extremely difficult.
The law is formally the Act of March 23, 1932 (Ch. 90, 47 Stat. 70). It is currently codified at 29 U.S.C. ch. 6, starting at 29 U.S.C. § 101 et. seq.