The U.S. Supreme Court case Pennsylvania v. Edwin Labron in 1995 revolved around the Fourth Amendment, which protects against unreasonable searches and seizures. The defendant, Edwin Labron, was convicted of murder based on evidence found in his car without a warrant after he was arrested outside his vehicle. He appealed this conviction arguing that the evidence should be suppressed because it was obtained unlawfully due to lack of a search warrant at the time of seizure. However, the Supreme Court ruled against him stating that if police have probable cause to believe there is contraband inside an automobile that has been stopped on the road or is readily mobile, they may search it without obtaining a warrant under what's known as "the automobile exception". This decision reaffirmed previous rulings by upholding law enforcement’s ability to conduct immediate searches when there are reasonable grounds for suspicion - even if they do not possess an official court-issued document permitting them to do so.

In the dissenting opinion for Pennsylvania v. Edwin Labron, Justice Stevens argued that the majority's decision to allow warrantless searches of automobiles based solely on probable cause was a significant departure from established Fourth Amendment jurisprudence. He contended that this ruling effectively eliminated the requirement for police officers to obtain a search warrant before searching an automobile, even when it would be reasonably practicable to do so. This, he believed, undermined one of the fundamental protections provided by the Fourth Amendment - protection against unreasonable searches and seizures without judicial oversight or approval. Furthermore, he criticized the majority's reliance on historical practices rather than constitutional principles in reaching their decision.