BRITISH COLUMBIA - The Supreme Court of Canada has given a green light to political advertising on the sides of transit vehicles, ruling that a bus is a "public place" where free expression should rarely be curtailed.

The court ruled 8-0 against a policy that two B.C. mass transit agencies, TransLink and BC Transit, invoked to refuse political ads that they feared might make passengers uncomfortable.

"I have some difficulty seeing how an advertisement on the side of a bus that constitutes political speech might create a safety risk or an unwelcoming environment for transit users," Madam Justice Marie Deschamps said for the court.

"Citizens, including bus riders, are expected to put up with some controversy in a free and democratic society."

The court concluded that an advertising ban could be justified only to screen out ads that could create a dangerous, offensive or hostile environment, such as ones extolling the virtues of terrorism.

"It does not follow that government has to abandon any notion of taste," said Chris Sanderson, a lawyer for the B.C. Civil Liberties Association. "What government does have to be able to do is justify any limitations it puts on free expression."