In Trupiano et al. v. United States (1947), the U.S. Supreme Court overturned a conviction for operating an unregistered distillery, ruling that evidence obtained in violation of the Fourth Amendment's prohibition against unreasonable searches and seizures was not admissible in court. The case involved Carmine Trupiano and Sam Mascio who were convicted based on evidence seized without a warrant from their illegal distillery operation during their absence. In its decision, the Court emphasized that law enforcement officers must obtain warrants when they have time to do so before conducting searches or seizing property; failure to do this would violate constitutional rights even if there is probable cause for suspicion of criminal activity.

In the dissenting opinion for Trupiano et al. v. United States, Justice Frank Murphy argued that the majority's decision to uphold a warrantless search and seizure was in violation of Fourth Amendment rights. He contended that law enforcement should be required to obtain a warrant whenever practicable, even if they have probable cause or exigent circumstances exist. In his view, exceptions to this rule should only occur when there is an immediate danger or risk of evidence being destroyed before a warrant can be obtained. He expressed concern over the potential erosion of constitutional protections against unreasonable searches and seizures if police were given too much discretion in deciding when it is reasonable not to get a warrant.