In the United States v. King case of 1968, the Supreme Court ruled on issues related to search and seizure under the Fourth Amendment. The defendant, King, had been convicted for possessing an unregistered firearm based on evidence obtained during a warrantless search by federal officers at his residence. He appealed this conviction arguing that it violated his Fourth Amendment rights against unreasonable searches and seizures as no warrant was issued prior to searching his home. However, the Supreme Court upheld King's conviction stating that he had voluntarily consented to the search when he allowed officers into his home without demanding a warrant first. This ruling established precedent regarding voluntary consent in situations involving potential violations of Fourth Amendment rights.

In the dissenting opinion for United States v. King, the justice argued that the majority's decision to allow evidence obtained through a warrantless search of an individual's home violated Fourth Amendment protections against unreasonable searches and seizures. The justice contended that there were no exigent circumstances justifying such a search in this case, as law enforcement officers had ample time to obtain a warrant but chose not to do so. Furthermore, they disagreed with the majority’s interpretation of “consent” given under duress or threat by police presence. They believed it was inconsistent with previous court rulings which emphasized voluntary consent without coercion or intimidation from law enforcement officials. In their view, allowing such practices would undermine citizens' constitutional rights and set a dangerous precedent for future cases involving similar issues.