It is the duty of the police department to enforce the provisions of this chapter; provided, that the finance director is authorized and directed to employ a parking patrol officer or officers for the purpose of enforcing this chapter and the patrolled parking area, the metered parking zones and areas, and such other areas as may be directed by the finance director. The parking patrol officer shall have the authority to issue tickets for violation of this chapter on forms furnished by the police department and so authorized by special commission of the chief of police. Parking patrol officers shall have no further police powers and shall be employees of the finance director and not members of the police department.