A.   Duty Of Police Department: It shall be the duty of the police department to enforce the street traffic regulations of this city, and all of the state vehicle laws applicable to street traffic in this city, to make arrests for traffic violations, to investigate accidents and to cooperate with the public works director and other officers of the city in the administration of the traffic laws and in developing ways and means to improve traffic conditions, and to carry out those duties specially imposed upon said department by the traffic provisions of this code. (2003 Code § 10-02-01)
   B.   Investigation Of Accidents And Reports: It shall be the duty of the police department to investigate traffic accidents, to arrest and to assist in the prosecution of those persons charged with violations of law causing or contributing to such accidents. The police department shall maintain a suitable system of filing traffic accident reports by location. Such reports shall be available for the use and information of the public works director. (2003 Code § 10-02-02)
   C.   Emergency And Experimental Regulations:
      1.   The chief of police, by and with the approval of the public works director, hereby is empowered to make regulations necessary to make effective the provisions of the traffic laws of this city, and to make and enforce temporary or experimental regulation to cover emergencies or special conditions. No such temporary or experimental regulation shall remain in effect for more than ninety (90) days without city council approval.
      2.   The public works director may test traffic control devices under actual conditions of traffic. (2003 Code § 10-02-03)