We compile our own dataset using the following sources: Chicago Tribune, Chicago Sun-Times, Homicide Watch Chicago (no longer updated), DNAInfo Chicago (out of business), Chicago Redeye Homicide Tracker (no longer updated), NBC5 Chicago, Chicago Tribune’s Shooting Tracker & Homicide Tracker, Cook County Medical Examiner, CPD’s Historical Data Set, City of Chicago Data Portal, Chicago Police Department Arrest Record Search and CPD CLEARMAP.

Community areas and neighborhoods are determined by the Chicago Tribune’s Boundaries App and/or Crimeisdown.com’s most excellent Incident Map.

Editor’s note: All murders are homicides, but not all homicides are murders. We count homicides, whereas the CPD counts murders. A homicide, or a non-fatal shooting, regardless of type or by whom, within the city limits of Chicago counts towards our total metric, including anything on the expressways. CPD-involved, ISP-involved and justifiable homicides all count. Reckless homicides may count if the Medical Examiner rules that the cause of death was a homicide. Suicides do not count. Additional definitions can be found on the Glossary page.