In 1991, the Supreme Court of Canada issued a very clear judgment in support of free expression in the public areas of airports, in Committee for the Commonwealth of Canada v. Canada,  1 SCR 139. The Court reiterated that speech cannot be censored just because some people may find it offensive. In particular, the Court held that peaceful expression of opinion is permitted in the public areas of airports, which are owned by government. All members of the public (not just travelling passengers with tickets) have access to these public, government-owned areas, and are free to express their opinion peacefully in public spaces.
In spite of the Court’s ruling in Commonwealth, the Calgary Airport Authority charged eight peaceful protesters with trespassing in October 2011, claiming that the airport is private property (all while admitting that the airport is owned by government, and that the Calgary Airport is a tenant).
The Justice Centre defended the protesters’ free expression rights in the Provincial Court of Alberta. On July 15, 2013, the Court acquitted the protesters of the trespassing charges, in R. v. Booyink. Judge Allan Fradsham noted that the protesters were peaceful and well-behaved, and did not interfere with any of the airport’s operations. He upheld their right to express their opinions in the public sections of the Calgary International Airport, based on the 1991 Supreme Court of Canada decision in Commonwealth.