WASHINGTON, Jan. 24 – The Supreme Court ruled on Monday that in making a routine traffic stop, the police can permit a trained dog to sniff the car for drugs without the need for any particular reason to suspect the driver of a narcotics violation.
The 6-to-2 decision set aside a ruling by the Illinois Supreme Court, which held in 2003 that a state trooper who had stopped a man for speeding had broadened the scope of the encounter beyond constitutional limits by having the dog sniff the car. The dog alerted the police to the trunk, which contained $250,000 worth of marijuana. The addition of the dog impermissibly turned a traffic stop into a drug investigation, the Illinois court said.
In the majority opinion on Monday, Justice John Paul Stevens said the dog’s sniff did not amount to an unconstitutional search because it did not prolong the 10-minute traffic stop and did not violate any “legitimate interest in privacy” a driver could have in carrying contraband.
“A dog sniff conducted during a concededly lawful traffic stop that reveals no information other than the location of a substance that no individual has any right to possess does not violate the Fourth Amendment,” Justice Stevens said. The Fourth Amendment prohibits “unreasonable” search and seizure.
The opinion suggested that a dog sniff was not a search at all because it detects only contraband and therefore cannot compromise a law-abiding person’s privacy. “Official conduct that does …