The Criminal Investigations Division is a specialized group of deputies that investigates felony crimes committed in unincorporated Jefferson County and files cases with the District Attorney's Office. 

Drug Enforcement Administration

The Jefferson County Sheriff's Office contributes personnel and manpower to the Drug Enforcement Administration (DEA). The DEA investigates individuals and groups involved in illegal-drugs trafficking and associated criminal enterprises.

Critical Incident Response Team

The First Judicial District has used a multi-agency Critical Incident Response Team (CIRT) since 1990 to investigate any discharge of a firearm by a law enforcement officer which resulted in injury. Legislation passed in 2015 that requires all Colorado law enforcement agencies and district attorneys to develop a Critical Incident protocol for participating in a multi-agency team to conduct the investigation and review.

Jefferson County Regional Crime Laboratory

The Jefferson County Regional Crime Laboratory (JCRCL) is a regional lab providing forensic services to law enforcement agencies in Jefferson County.  The JCRCL provides assistance in the areas of drug chemistry, latent print examination, forensic biology, firearms examination, digital photography/video processing.  The lab also provides training to all new deputy recruits through the Jefferson County Combined Regional Training Academy, to experienced officers and deputies through crime scene training programs, and to citizen and student groups.