The primary function of the Investigative Services Division is to conduct the follow-up investigation after a crime has been reported. The goal is to identify the perpetrators of the crime to assist the District Attorney's Office in the successful prosecution of the suspect(s).

The Investigative Services Division also provides support to victims of crimes during the course of an investigation. The crime victims and the community both benefit from the prosecution and punishment of criminals.

Many investigations can be completed in a matter of weeks, whereas other investigations may take years before they are solved.

Every attempt is made to prioritize their work so that cases involving injured persons, threat to personal safety or significant property loss receive the most immediate attention.

The Street Crimes Unit and Narcotics Unit are also assigned to the Investigations branch. While the Narcotics Unit focuses on drugs and vice investigations, the Street Crimes Unit concentrate their attention on gang activity, intelligence investigations, and the concerns surrounding probationers.