In its recent decision in R. v. Chehil, 2013 SCC 49, the Supreme Court of Canada dismissed an appeal from a decision of the Nova Scotia Court of Appeal involving a search of a suspect by police using a drug-sniffing dog. The Court, in a unanimous decision written by Justice Karakatsanis, found that sniff searches that are based on reasonable suspicion are compliant with the Charter. Building on its decision in R.v. Kang-Brown, 1 S.C.R. 456, and R. v. A.M.,  1 S.C.R. 569, the Court balanced the travelling public’s privacy interests against the public interest in apprehending those who transport and traffic drugs. The Court concluded that the use of a properly deployed drug detection dog was a search that was authorized by law and reasonable on the lower threshold of “reasonable suspicion” rather than the more stringent threshold of “reasonable and probable grounds”. Because they are minimally intrusive, narrowly targeted, and can be highly accurate, sniff searches may be conducted without prior judicial authorization.
The Court stated specifically at paragraph 29, “Reasonable suspicion must be assessed against the totality of the circumstances. The inquiry must consider the constellation of objectively discernible facts that are said to give the investigating officer reasonable cause to suspect that an individual is involved in the type of criminal activity under investigation. This inquiry must be fact-based, flexible, and grounded in common sense and practical, everyday experience.”