Last week, protest erupted in the streets of major American cities as a grand jury failed to indict a New York police officer who killed an unarmed black man. Eric Garner's chokehold death was captured on video, sparking tens of thousands of protesters to disrupt traffic chanting Garner's last words: "I can't breathe."

Police have acted with impunity in Canadian cities, too, most recently when a teenager filmed Vancouver police as they shot and killed 51-year-old Phuong Na Du at an East Vancouver intersection. An investigation is underway.