The Detective, Narcotics, Crime Lab, and Warrant Units comprise Investigative Services.

Detectives

The Detective Unit investigates criminal activity throughout Hennepin County, apprehends people suspected of committing crimes and prepares cases for prosecution. The unit handles all criminal investigations for municipalities that do not have their own police departments, as well as for larger municipalities whose police departments have limited investigative resources to assist their police departments with homicide and other major crime investigations. Sheriff's detectives are assigned to the FBI Joint Terrorism Task Force, the Minnesota Internet Crimes Against Children Task Force, and the Hennepin County Attorney's Adult, Juvenile and Gang Prosecution Units.

Narcotics

The Narcotics Unit, based in downtown Minneapolis, goes after mid-level dealers. The Narcotics Unit is a partner in several successful drug task forces: the DEA Drug Task Force; the Southwest Hennepin Drug Task Force (which includes the Sheriff's Office and the Eden Prairie, Edina and Minnetonka Police Departments); and the new West Metro Drug Task Force (which includes the Sheriff's Office, the Medina, Mound and Orono Police Departments, and the West Hennepin Department of Public Safety).

Crime Lab

Based in downtown Minneapolis, the Crime Laboratory Unit provides crime scene processing and forensic science services to all Hennepin County law enforcement agencies. The Crime Lab is American Society of Crime Laboratory Directors/Laboratory Accreditation Board (ASCLD/LAB) accredited and the ASCLD/LAB also certified the unit in three of the major forensic science disciplines of analysis: latent fingerprints, DNA/biology and crime scene processing. The unit's crime lab technicians, the sheriff's deputies who collect evidence at crime scenes, are the first team of crime scene investigators in Minnesota to earn ASCLD/LAB certification, and just the thirteenth in the entire nation.

Warrants

The Warrant Unit receives, records, manages and serves arrest warrants and other court orders issued by Minnesota's Fourth Judicial District, as well as warrants and orders issued by outside jurisdictions for people located in Hennepin County. Sheriff's deputies working for the unit physically serve warrants, which involves investigating suspects' whereabouts, locating and arresting them. Warrant Unit deputies drive and fly throughout the United States to pick up and return to Minnesota suspects arrested by other law enforcement agencies and wanted in Hennepin County.