When Dusty is brought to campus, he walks the hallway, sensitive nose in the air, sniffing for contraband. When he gets a scent from a locker or a car he simply stops and sits down. That sends a message to his trainer that something he doesn't like is behind the door, in a purse, under the rug, in a glove compartment. And it's also what makes the search constitutional, says Montana School Board Association attorney Elizabeth Kaleva. Though the Fourth Amendment to the U.S. Constitution guarantees citizens protection from illegal search and seizure, school officials, Kaleva says, have a greater flexibility when it comes to searching lockers, classrooms, cars parked on school property and even personal possessions.
Reasonable suspicion lowers the bar by reducing the expectation of privacy.
That lesser standard is also why the school board uses a private company for its searches and not the sheriff's office, which also has a trained dog on staff, but which must abide by the probable cause standard. State courts in Louisiana and Florida, for instance, have upheld the use of drug-sniffing dogs in schools. The Fifth and Tenth Circuit Courts of Appeals also have upheld the use of dogs on school campuses, generally ruling that dogs trained to simply sniff the air for nearby contraband is not a constitutional violation. Arbitrarily opening lockers, purses and cars and allowing a trained dog to go at them with their well-trained noses probably would be a violation, however. But in the case of Dusty, and other detection dogs like him, there is no arbitrary rummaging around through anyone's belongings, just a simple walk-through with nose in the air and on full alert.