The Criminal Investigations Division, or C.I.D., investigates persons and property crimes occurring in the City of Valparaiso. In addition to the investigation and prosecution of criminals, these professionals are responsible for crime scene investigations, administration of truth verification devices, gathering and compiling of criminal intelligence and evidence processing. Investigators are assigned major crimes such as homicides, rapes, robberies, and home invasions, as well as property crimes such as auto thefts, burglaries, and financial or fraud cases like pyramid schemes and credit card scams.

The Criminal Investigations Division also is the lead division in all death cases to include homicide, suicide and traffic related deaths. These investigations consist of interviewing suspects, victims, and witnesses; analyzing information for validity, reliability, and accuracy; and compiling a comprehensive and factual case file to be presented in court.