In a ruling [13] last Friday, the Canadian Supreme Court held that the use of drug-sniffing dogs in a random search of an Ontario school was unconstitutional. The decision should result in an end to random drug dog searches across the country -- except at borders and airports, where customs officials have free rein.

The case began in 2002, when police visited St. Patrick's High School in Sarnia, in the southwestern part of the province. Police confined students to their classrooms, while taking their backpacks to an empty gym. The dog alerted on one backpack, and one youth who was identified only by his initials was subsequently charged with possession of marijuana and psychedelic mushrooms.
Police admitted they had no search warrant nor even a tip that drugs were present at the school. Instead, they said, they were responding to a long-standing open invitation from school officials.
The trial judge in the case granted a motion to exclude the seized drugs as evidence and acquitted the youth. Prosecutors appealed, but the Ontario Court of Appeal in 2004 upheld the trial judge, saying the sniffing of backpacks by the drug dog amounted to "a warrantless, random search with the entire student body held in detention."
Crown lawyers argued unsuccessfully that being sniffed by a drug dog does not constitute a search. Odors in the public air are not private, and a drug dog detecting contraband by smell should be viewed as similar to police officers detecting an odor in the air, they argued.
That argument would have flown in the United States, where the Supreme Court has okayed the use of drug dogs in random searches, saying a drug dog sniff did not amount to a search. But it didn't fly in the Canadian courts. Now, police will not be able to conduct random searches with drug dogs in public places, such as churches, schools, and shopping malls.