The use of a drug-sniffing police dog on a homeowner’s front porch to detect the presence of drugs inside the residence constitutes a search within the meaning of the Fourth Amendment. While on Jardines’ front porch, police used a dog to detect the presence of narcotics. When the dog alerted to the presence of drugs, police used this information to obtain a search warrant. Inside the house police found marijuana plants. Jardines challenged the use of the forensic narcotic dog as an illegal search. Held: Use of the dog constituted a search. The Fourth Amendment protects the home against unreasonable government intrusion. A resident’s right to retreat into his own home and be free of such intrusion would have little value if the government could stand on the home’s porch or side yard and search for evidence; this area (the curtilage) is part of the home for Fourth Amendment purposes. Thus, the dog sniffing investigation took place in a constitutionally protected area. Further, it was accomplished without express or implied consent. There is no customary invitation to enter onto another’s property to explore the area immediately around the home for incriminating evidence. “The scope of a license–express or implied–is limited not only to a particular area but also to a specific purpose.” Cases such as Whren v. United States (1996) 517 U.S. 806, are not contrary to the present decision because they hold that a stop or search that is objectively reasonable is not vitiated when an officer’s motive for the stop/search differs from the validating reason. Here, the officers’ conduct was not objectively reasonable because they had no license to conduct a search.