The night watch, though relatively effective, only served during the night. During the day, the responsibility of protecting innocent citizens and apprehending criminals fell to the constables and marshals. Soon a day watch was implemented in many areas. In extreme situations, such as riots, the colonial communities often had to call out the militia. Riots, a common disturbance in colonial America, occurred for many reasons including to contest elections, to protest economic conditions, or to enforce standards of morality. Even at the first sign of a riot the mayor or some other official would appear and literally read the riot act to the assembled crowd.