Open this photo in gallery: A pro-Palestinian poster is attached to a parking sign across the street from the University of Montreal metro station in Montreal, on Nov. 14.Christinne Muschi/The Canadian Press What is protected by the right to free speech? And what isn’t? Let’s start with an easy case. At a pro-Palestinian protest on Sunday inside Toronto’s Eaton Centre, a masked man was filmed pointing at someone standing next to a police officer. “I will lay you to sleep,” he shouted. “I’ll put you six feet deep.” Threatening physical harm to someone, on camera, with the police right there,...