Gangs Datasets Questions? Get in touch LEADS Gang File Summary Data free LEADS Gang File Summary Data free Counts of individuals added into the LEADS (Law Enforcement Agencies Data System) Gang File by Illinois state and local police in each year since 1993. Learn more Source Illinois State Police Dates 1993 to 2018 Learn more Cook County Regional Gang Intelligence Database free Cook County Regional Gang Intelligence Database free A snapshot of the gang database maintained by the sheriff’s office and jail in Cook County, Illinois, along with other law enforcement agencies. Personal identifiers have been removed. Learn more Source Cook County Sheriff’s Office Dates June 2018 Learn more Chicago Police Department Data on Gang Members free Chicago Police Department Data on Gang Members free This dataset contains descriptive information on individuals that the Chicago Police Department has classified as gang members. Learn more Source Chicago Police Department Learn more