Fewer local police agencies report [FBI Supplemental Homicide Report data, which contains information on victims and offenders] than report standard [Uniform Crime Reporting data, which does not].
“Felon killed by police” refers narrowly to justifiable police homicides, and “unjustifiable homicide by police” is not a classification. This means it’s difficult to combine unjustifiable police homicides — which could be listed as crimes elsewhere in the database — with “justifiable” police homicides.
If the legality of a police homicide is in question, it may not be reported to the FBI SHR until the investigation is resolved. If the investigation concludes in a new reporting year, the old SHR data may not be updated, regardless of whether the killing was found to be justifiable or not. Criminology professor Geoff Alpert of the University of South Carolina, an expert on police violence, said he has “never seen a department go back and audit their numbers and fix them.” (In a statement provided in response to emailed questions, the FBI confirmed that it generally does not reopen master data files to add or correct reports.)
Killings in federal jurisdictions, such as federal prisons or military bases, are not included in the database.