An Illinois state trooper stopped respondent for speeding on an interstate highway, and the stop was concededly lawful at its inception. While the first trooper was writing a warning ticket, a second trooper arrived with a narcotics-detection dog and walked the dog around the exterior of respondent's car. The dog alerted at the trunk, officers searched the trunk, found marijuana, and arrested respondent. The entire incident lasted less than 10 minutes, and the Court accepted the state court's conclusion that the stop was not improperly prolonged.
Issue
Does the Fourth Amendment require reasonable, articulable suspicion to justify using a drug-detection dog to sniff the exterior of a vehicle during a lawful traffic stop that is not extended beyond the time reasonably required to complete the stop?
Rule
Official conduct that does not compromise any legitimate interest in privacy is not a search subject to the Fourth Amendment. Accordingly, the use of a well-trained narcotics-detection dog during a lawful traffic stop generally does not implicate legitimate privacy interests, because it reveals only the presence or absence of contraband; however, a traffic stop can become unlawful if it is prolonged beyond the time reasonably required to complete its mission.
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10 practice questions + 4 AI-graded essays on this case
One of 10 multiple-choice questions for this case. Pick an answer to see why.
On Interstate 25 near Denver, Officer Lena Ortiz lawfully stops Marcus Hale for driving 15 miles over the speed limit. While Ortiz is checking Marcus's license and writing a citation, another officer walks a well-trained narcotics-detection dog around the exterior of Marcus's SUV; the dog alerts before the citation process is complete, and the entire stop lasts eight minutes.
Marcus moves to suppress the drugs found in the cargo area, arguing that police needed reasonable suspicion of drug activity before using the dog. How should the court rule?
Explanation. The majority held that official conduct that does not compromise a legitimate privacy interest is not a Fourth Amendment search. A well-trained narcotics-detection dog's sniff of a vehicle's exterior during a lawful traffic stop generally reveals only the presence or absence of contraband, in which there is no legitimate privacy interest. Because the stop here was lawful and not extended beyond the time reasonably required to complete the traffic mission, no reasonable suspicion of drug activity was required for the sniff.