Illinois v. Caballes, 543 U.S. 405 (2005)

In Illinois v. Caballes, 543 U.S. 405 (2005), the underlying events began when Illinois State Trooper Daniel Gillette stopped Roy I. Caballes for speeding on an interstate highway. During the stop, Trooper Gillette contacted a dispatcher, which was overheard by Trooper Craig Graham, a member of the Illinois State Police Drug Interdiction Team. Graham arrived at the scene with a narcotics-detection dog while Gillette was writing a warning ticket. As the dog was walked around Caballes' vehicle, it alerted at the trunk, prompting the officers to search it. They discovered marijuana inside, leading to Caballes' arrest. The entire encounter lasted less than ten minutes. Procedurally, Caballes was convicted of a narcotics offense and sentenced to 12 years in prison along with a substantial fine. He filed a motion to suppress the evidence obtained from the dog sniff and to quash his arrest, arguing that the officers had unlawfully prolonged the traffic stop. The trial court denied his motion, asserting that the stop was not extended beyond what was necessary for issuing the warning ticket and that the dog’s alert provided probable cause for the search. However, the Illinois Appellate Court affirmed the conviction, while the Illinois Supreme Court reversed it, determining that the canine sniff was conducted without specific and articulable facts indicating drug activity, thus unlawfully expanding the scope of the routine traffic stop. The case reached the U.S. Supreme Court on a writ of certiorari, focusing on whether the Fourth Amendment requires reasonable, articulable suspicion to justify the use of a drug-detection dog during a legitimate traffic stop. The Supreme Court accepted the premise that the officer conducting the dog sniff had no prior information about Caballes other than the speeding violation. The Court acknowledged that while a lawful seizure can become unconstitutional if it is executed in a manner that unreasonably infringes on protected interests, the Illinois Supreme Court's ruling raised questions about the legality of the dog sniff conducted during the traffic stop.

Whether the Fourth Amendment requires reasonable, articulable suspicion to justify using a drug-detection dog to sniff a vehicle during a legitimate traffic stop.

The judgment is affirmed.