The Investigations Division is comprised of twelve personnel, and is headed by a captain, lieutenant, and a sergeant.  The detectives are responsible for investigating crimes that occur within the City of Morristown, ranging from vandalism of property to crimes against persons, such as assaults or murders.  The unit also handles internal affairs investigations and background investigations of potential employees.  Detectives investigate crimes committed by or against both juveniles and adults.

Several investigators are trained in specialized fields such as juveniles, arson, sex crimes, auto theft, and criminal intelligence.  One investigator is assigned the responsibility of the Crime Scene Investigations / Forensics Team, and three are assigned to the Narcotics/Vice Unit.