The Criminal Investigations Unit (CIU) is comprised of six detectives, three School Resource Officers two officers in the Targeted Response Unit (TRU), and a task force officer assigned to the Drug Enforcement Administration (DEA).

Responsibilities

The Criminal Investigations Unit's detectives are responsible for the investigation of cases not initially cleared by the responding patrol officers. In order to maximize available investigative resources, each report is reviewed based on a series of factors. Cases are either assigned for follow-up or placed in an inactive file pending additional information.

McHenry County Major Investigation Assistance Team

Since 1997, the Crystal Lake Police Department has been a member of the McHenry County Major Investigation Assistance Team (MIAT). Upon request of the Chief of a member agency, this unit provides assistance in the investigation of a homicide or other exceptionally heinous crime within McHenry County. MIAT provides specially trained investigators and equipment not normally available to individual agencies.