Also known as: dog sniff · dog sniffs · canine sniff · canine sniffs · dog sniff for contraband · canine sniff search · dog sniff doctrine
Written by attorneys · grounded in primary & secondary sources — see below
A law-enforcement investigative technique in which officers expose personal property or a vehicle to a trained narcotics-detection dog. The technique reveals only the presence or absence of contraband and therefore does not constitute a search under the Fourth Amendment when performed without prolonging a lawful detention.
Dwight Dorsey was pulled over for a broken taillight. While the officer verified the registration, a canine unit arrived and walked the dog around the car. The dog alerted at the trunk within the time required to complete the traffic citation. Officers opened the trunk and found marijuana. The sniff supplied probable cause for the search because it occurred without extending the stop.
Danielle Dixon arrived at the airport with a checked bag. Officers with reasonable suspicion seized the bag and held it for nearly two hours while awaiting a narcotics dog. The dog alerted and officers obtained a warrant. The prolonged detention of the bag violated the Fourth Amendment even though the subsequent sniff itself was not a search.
Select any source to read its text and confirm it supports the definition.
Derek Douglas drove through a city checkpoint set up to interdict drugs. Officers directed all vehicles to stop while a dog walked the line of cars. The dog alerted on Douglas's trunk. The checkpoint program was held unconstitutional because its primary purpose was general crime control rather than roadway safety.
No. A dog sniff conducted during a lawful traffic stop that does not prolong the stop beyond the time needed to address the traffic violation does not require reasonable suspicion of drug activity. The sniff reveals only the presence or absence of contraband in which there is no legitimate privacy interest.
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Detaining luggage for a dog sniff on reasonable suspicion must remain brief. A detention approaching ninety minutes exceeds the limited scope permitted by reasonable suspicion and becomes an unreasonable seizure even though the sniff itself is not a search.
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No. A trained narcotics dog's sniff of luggage in a public place is not a search because it discloses only the presence or absence of contraband and does not reveal other private information about lawful contents.
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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…