In Muniz et al. v. Hoffman, the U.S. Supreme Court ruled in favor of the National Labor Relations Board (NLRB), upholding its authority to prevent unfair labor practices even when those involved are undocumented immigrants. The case arose after a group of employees were fired from their jobs for unionizing activities at Sure-Tan Inc., a leather goods manufacturer in Chicago, and subsequently reported by their employer to immigration authorities leading to deportation proceedings against them. The NLRB ordered reinstatement with backpay for these workers upon finding that they had been unjustly terminated due to their union involvement - an order contested by Sure-Tan on grounds that it would reward illegal immigration status. The Supreme Court held that while the Immigration and Nationality Act prohibits employment of illegal aliens, this does not strip such individuals off protections under the National Labor Relations Act (NLRA). It further clarified that although awarding backpay might seem like rewarding unlawful presence in the country, it is necessary as a deterrent against employers exploiting immigrant workers' vulnerability or using immigration laws as anti-union strategy.

In the dissenting opinion for Muniz et al. v. Hoffman, Justice Douglas argued that the majority's decision was a departure from established precedent and an overreach of judicial power. He contended that the Court had no authority to create exceptions to laws passed by Congress, as it did in this case by denying backpay to undocumented workers who were illegally fired for union activities. According to Douglas, such decisions should be left up to legislative bodies rather than courts. He also pointed out that while immigration law prohibits employment of illegal aliens, labor law protects all employees regardless of their legal status - thus creating a conflict between two federal statutes which he believed should have been resolved in favor of protecting worker rights.