District Attorney Investigators perform a broad range of investigations including investigations into specialized areas not handled by other local law enforcement agencies; investigations into areas targeted by the state; investigations to assist the operations of other departments/programs; and assistance in trial preparation investigations.

Investigators from the District Attorney's Office are part of the critical incident response team called out when an incident involving the use of "lethal force" by a peace officer occurs in the county. DA investigators are also called upon to conduct investigations into suspected misconduct by government officials, public employees or local agencies.

District Attorney Investigators also assist prosecutor staff in preparing for various court processes on cases which were initially investigated by other law enforcement agencies. These tasks range from interviewing witnesses, serving court documents, collecting additional evidence, trial preparation, and many other tasks.