In 1980, Drug Enforcement Administration (DEA) agents began investigating Ronald Dale Dunn and Robert Lyle Carpenter (defendants) after learning that Carpenter had purchased paraphernalia used for making drugs. The DEA agents secured warrants from a Texas judge to place tracking devices in items ordered by Carpenter. On November 5, 1980, agents tracked the items to Dunn’s ranch. There were perimeter and interior fences on the ranch. A large barn about fifty yards from the home’s fence line had fencing, gates, and netting surrounding the entrance. Law enforcement entered the ranch without a warrant, crossed several fences, and looked into the barn. The DEA agent believed he smelled phenylacetic acid and saw a phenylacetone laboratory. The next day, the officers returned to the property to verify what they had seen and secured a warrant from a Federal Magistrate to search the ranch. On November 8, 1980, the officers searched the ranch, seized drugs and paraphernalia, and arrested Dunn. Dunn and Carpenter were convicted of violating 21 U.S.C. § 846 for the possession, manufacture, and/or distribution of amphetamine and phenylacetone. The Supreme Court granted certiorari to consider whether the barn was protected under the Fourth Amendment as part of the curtilage of the house.