The Missouri Supreme Court has unanimously ruled that detaining a motorist who is stopped for a traffic violation so his car can be checked by a drug-sniffing dog violates the Fourth Amendment. The case is similar to one in which the U.S. Supreme Court heard oral arguments last week, involving an Illinois motorist who was convicted of drug trafficking after a dog detected marijuana in his car.
In the context of public places such as airports and bus stations, the Supreme Court has held that the use of drug dogs does not constitute a "search" within the meaning of the Fourth Amendment. But detaining someone for the purpose of a canine exam may be a different story. In the Missouri case, the driver, Jose Granado, was held longer than necessary for the traffic violation, while the cop who pulled him over waited for the dog to arrive. "At the time the patrolman began the search," the Missouri Supreme Court ruled, "the purpose of the traffic stop already was complete, and a search could not be conducted without new and articulable suspicion that Granado had committed a crime." In the Illinois case, by contrast, the dog arrived while the cop was in the middle of writing a warning ticket.
In short, our Fourth Amendment rights may hinge on a dog's punctuality.