It shall be the duty of the chief of police, with such aid as may be rendered by other members 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 traffic accidents; to cooperate with the other officers and officials 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 by this title and the traffic ordinances of this city. (Ord. 50 §17, 1951).