The Arcata Police Department Investigations Unit is comprised of 1 Detective Sergeant and 1 Detective. The Detectives are responsible for follow-up investigation of all crimes, which are beyond the resources of the Patrol Division. They are also the liaison to the other investigative units in the county. The Detective investigates all "crimes against persons" cases. These are classified as
- Assault with a deadly weapon
- Sexual assault
- Domestic violence
- Battery
- Child abuse
- Elder abuse
- Terrorist threats
The Detectives also investigate property crimes involving burglary, theft, embezzlement, forgery, stolen vehicles, and vandalism. In addition to investigations, this unit provides services for special projects and long-term problem solving.