Also known as: dog sniff · canine sniff · canine sniffs · dog sniff search
Written by attorneys · grounded in primary & secondary sources — see below
An investigative technique in which a trained canine detects the odor of contraband from the exterior of a vehicle or container. The technique reveals only the presence or absence of illegal substances and therefore does not intrude on any legitimate privacy interest. When performed during a lawful detention and without adding time to that detention, the technique requires no separate justification such as reasonable suspicion or a warrant.
Destiny Davis was pulled over for a broken taillight. While the officer verified her license and registration, a second officer walked a trained narcotics dog around the exterior of the car. The dog alerted at the trunk without extending the stop. Officers then searched the trunk and found marijuana.
Dolores Diaz checked her suitcase at the airport. Officers with reasonable suspicion seized the bag and held it for ninety minutes before a dog could sniff it. The dog alerted and officers opened the suitcase. The extended seizure turned the brief investigative detention into an unreasonable one.
Select any source to read its text and confirm it supports the definition.
Dylan Duffy drove through a highway checkpoint aimed at intercepting drugs. Officers walked a narcotics dog around his car without individualized suspicion. The dog alerted and officers searched the vehicle. The program was held unconstitutional because its primary purpose was general crime control rather than roadway safety.
No. When the sniff occurs while officers are still handling the original traffic mission and does not add time to the stop, it is not a search and needs no separate suspicion. The dog reveals only the presence or absence of contraband, an item in which there is no legitimate privacy interest.
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The prolongation converts the stop into an unlawful seizure. Officers may not extend the detention even briefly beyond the time needed to complete the traffic mission unless they have independent reasonable suspicion of criminal activity.
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Yes. Courts treat a reliable canine alert as sufficient probable cause under the automobile exception, allowing a warrantless search of the vehicle and its containers. The alert itself supplies the fair probability that contraband is present.
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The detention must remain brief. A ninety-minute hold exceeds the limited scope permitted by reasonable suspicion and becomes an unreasonable seizure even though the subsequent dog sniff itself is not a search.
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…possesses a privacy interest in the contents of personal luggage that is protected by the Fourth Amendment. Id. , at 13. A "canine sniff" by a well-trained narcotics detection dog, however, does not require opening the luggage. It does not expose noncontraband items that otherwise would remain hidden from public view, as…