In a 5-4 decision, the Supreme Court of the United States held that extortion as defined by the Hobbs Act does not proscribe violence committed during a lawful strike for the purpose of inducing an employer's agreement to legitimate collective bargaining demands.
United States v. Enmons, 410 U.S. 396 (1973).
Philip D. Freeman,
Labor Law - Extortion as Defined by the Hobbs Act and Its Relation to Legitimate Labor Objectives,
Duq. L. Rev.
Available at: https://dsc.duq.edu/dlr/vol12/iss2/14