In the 1920 case of Burdeau v. McDowell, the United States Supreme Court ruled that evidence obtained by a private party without government involvement could be used in court, even if it was stolen or otherwise illegally obtained. The defendant, George Burdeau, had been indicted for fraud against the U.S. government and his personal papers were taken without his knowledge or consent by Frank J. McDowell who then turned them over to federal authorities as evidence of Burdeau's guilt. The Supreme Court held that since there was no governmental action involved in obtaining these documents - they were not seized through an illegal search conducted by law enforcement officials but rather taken unlawfully by a private citizen - their use did not violate the Fourth Amendment’s prohibition against unreasonable searches and seizures.

In the dissenting opinion for Burdeau v. McDowell, Justice Louis Brandeis argued that the Fourth Amendment should protect citizens from unlawful search and seizure by private individuals as well as government officials. He believed that if a private individual obtained evidence illegally and then handed it over to the government, this would still constitute an infringement of constitutional rights. In his view, allowing such actions would effectively encourage illegal behavior by private parties who could act without fear of legal consequences while providing authorities with information they might not have been able to obtain legally themselves. This interpretation was at odds with the majority's decision which held that only governmental action could violate Fourth Amendment protections against unreasonable searches and seizures.