The Division of Criminal Justice Services supports all facets of the state's criminal justice system. The agency provides direct training to law enforcement and other criminal justice professionals; oversees a law enforcement accreditation program; ensures Breathalyzer and speed enforcement equipment used by local law enforcement operate correctly; manages criminal justice grant funds; analyzes statewide crime and program data; provides research support; oversees county probation departments and alternatives to incarceration programs; and coordinates juvenile justice policy.

The agency also maintains criminal history records and fingerprint files and performs background checks for employment and licensure. The agency also administers the state's Sex Offender Registry; the Missing Persons Clearinghouse; the state's DNA Databank in cooperation with the New York State Police Forensic Investigation Center; and provides staff support to independently appointed commissions and councils, including the New York State Commission on Forensic Science, which monitors and accredits the state's forensic laboratories.