In the United States v. Dunn case of 1986, the Supreme Court ruled on a Fourth Amendment issue related to warrantless searches and seizures. The defendant, Dunn, was suspected of manufacturing illegal drugs in a barn located 50 yards from his residence but within its curtilage (the land immediately surrounding it). Law enforcement officers trespassed onto this property without a search warrant and observed incriminating evidence through open barn doors. They later obtained a search warrant based on these observations and arrested Dunn. The court had to decide whether this constituted an unreasonable search under the Fourth Amendment. The Supreme Court held that while homes are protected by the Fourth Amendment against unreasonable searches or seizures, not all buildings within its curtilage enjoy such protection if they do not serve as part of the home itself or support domestic activities associated with home life. In this case, since there were no intimate activities connected to residential living occurring in the barn where police found evidence of drug production - despite being inside Dunn's property line - it did not fall under constitutional protections for privacy rights granted by the fourth amendment.

In the dissenting opinion for United States v. Dunn, Justice Brennan disagreed with the majority's view that a barn located 50 yards from a fence surrounding a house was not part of the curtilage protected by Fourth Amendment rights against unreasonable searches and seizures. He argued that this interpretation contradicted previous court rulings which defined curtilage based on factors such as proximity to home, enclosure within an area surrounding home, use in activities associated with domestic life, and steps taken to protect privacy. According to him, all these factors indicated that Dunn’s barn was indeed part of his home’s curtilage since it was used for intimate activities related to his personal life and livelihood (methamphetamine production), enclosed within fences indicating expectation of privacy, and close enough to be considered an extension of his dwelling place. Therefore he believed law enforcement officers violated Dunn's Fourth Amendment rights when they trespassed onto his property without warrant or consent.