(a) It shall be the duty of the Police Department to investigate traffic accidents and to arrest and obtain prosecution of those persons guilty of violations of the law or ordinance causing or contributing to such accidents.
(b) The Police Department shall maintain a suitable system of filing traffic accident reports. Accident reports or cards referring to them shall be filed alphabetically by location. Such reports shall be available for the use and information of the Traffic Commission.
(c) Whenever the accidents at any particular location become numerous, the Police Department shall cooperate with the Service-Safety Director and Traffic Commission in conducting studies of such accidents and determining remedial measures.
(d) The Police Department shall receive and properly file all accident reports made to it.