The author focuses on changes in public perceptions of the police brought about by their suddenly visible role as the defender of the political legitimacy of the state, based on his experiences in investigating the Canadian authorities' invocation of the War Measures Act in October 1980 to deal with potential insurrections from large, politically organized minorities. This analysis questions several assumptions about the police role and concludes that certain police operations in political crises appear to be clearly illegal, even before being declared unwarranted. Over 90 references are supplied.