Wait, "dangerous" or "suspected dangerous"? Because most of the people in jail (not to be confused with prison/penitentiary) are not there for anything dangerou

Wait, "dangerous" or "suspected dangerous"? Because most of the people in jail (not to be confused with prison/penitentiary) are not there for anything dangerous to begin with. A policeman decided they they should be locked up and that policeman doesn't need any particularly good reason for it.