The U.S. Supreme Court case National Labor Relations Board v. Donnelly Garment Co., et al., 1946, revolved around the issue of unfair labor practices and collective bargaining rights. The National Labor Relations Board (NLRB) accused Donnelly Garment Company and its affiliate, Donnelly Garment Workers Union, of violating the Wagner Act by restraining employees' rights to self-organization and representation through an independent union - International Ladies' Garment Workers Union (ILGWU). The NLRB ordered the company to cease recognizing or dealing with its affiliated union as a representative for its employees unless it was certified under the act's provisions; however, this order was set aside by lower courts on appeal. In a unanimous decision led by Justice Wiley Rutledge, the Supreme Court reversed these decisions stating that substantial evidence supported NLRB's findings that both entities had engaged in unfair labor practices which violated Section 8(1) & (2) of Wagner Act. It held that employers cannot interfere with their workers’ right to choose their own representatives for collective bargaining purposes nor support a labor organization over another one without infringing upon employee rights protected under federal law.

In the dissenting opinion for the case National Labor Relations Board v. Donnelly Garment Co., Justice Frankfurter argued that the majority's decision was based on a misinterpretation of labor law and an overreach of judicial power. He contended that it is not within the court's jurisdiction to decide what constitutes "good faith" bargaining, as this should be left to negotiation between employers and employees or their representatives. Furthermore, he disagreed with the majority’s view that refusing to bargain with a minority union constituted unfair labor practice under Section 8(1) of The Wagner Act (National Labor Relations Act). According to him, such interpretation would force employers into multi-unionism which Congress never intended when drafting NLRA. He also criticized how NLRB handled its role in promoting collective bargaining by imposing sanctions instead of mediating disputes impartially.