No minor under the age of eighteen years shall loiter, congregate, gather in groups or roam or be upon the streets or public places of the City between the hours of midnight and 5:00 a.m. of the following morning. The following shall constitute valid exceptions to the operation, application, and requirements of this curfew:
(a) At any time, if the minor is accompanied by a parent, guardian, or person in charge of such minor or some other responsible person over twenty-one years of age who has been given permission by such parent, guardian, or person in charge to accompany the minor; or
(b) At any time, if the minor is upon an emergency errand or legitimate business directed by his parent or legal guardian; or
(c) If the minor is legally employed, for the period from one-half hour before to one- half hour after work, while going directly between his or her home and place of employment. To come under this exception, the minor must be carrying a written statement from the employer attesting to the place and hours of employment.