Although Congress instructed the Attorney General in 1994 to compile and publish annual statistics on police use of excessive force, this was never carried out, and the
Federal Bureau of Investigation does not collect these data. Consequently, no official national database exists to track such killings. This has led multiple non-governmental entities to attempt to create comprehensive databases of police shootings in the United States. The
National Violent Death Reporting System is a more complete database to track police homicides than either the FBI's Supplementary Homicide Reports (SHR) or the
Centers for Disease Control's
National Vital Statistics System (NVSS). This is because both the SHR and NVSS under-report the number of police killings.
Government data collection Through the
Violent Crime Control and Law Enforcement Act of 1994, specifically Section 210402, the U.S. Congress mandated that the
attorney general collect data on the use of excessive force by police and publish an annual report from the data. However, the bill lacked provisions for enforcement. Two national systems collect data that include homicides committed by law enforcement officers in the line of duty. The FBI maintains the
Uniform Crime Reporting Program (UCR), which relies on state and local law enforcement agencies voluntarily submitting a SHR. Records in the NVSS did not consistently include documentation of police officer involvement. The UCR database did not receive reports of all applicable incidents. The authors concluded that "reliable estimates of the number of justifiable homicides committed by police officers in the United States do not exist." The Death In Custody Reporting Act required states to report individuals who die in police custody. It was active without enforcement provisions from 2000 to 2006 and restored in December 2014, amended to include enforcement through the withdrawal of federal funding for non-compliant departments. An additional bill requiring all American law enforcement agencies to report killings by their officers was introduced in the U.S. Senate in June 2015. According to the Centers for Disease Control and Prevention (CDC), based on data from medical examiners and coroners, killings by law enforcement officers (not including legal executions) was the most distinctive cause of death in Nevada, New Mexico, and Oregon from 2001 to 2010. In these states, the rate of killings by law enforcement officers was higher above national averages than any other cause of death considered. The database used to generate those statistics, the CDC WONDER Online Database, has a U.S. total of 5,511 deaths by "Legal Intervention" for the years 1999–2013 (3,483 for the years 2001–2010 used to generate the report) excluding the subcategory for legal execution.
Crowd-sourced projects to collect data Mainly following public attention to police-related killings after several well-publicized cases in 2014 (e.g.,
Eric Garner,
Michael Brown, and
John Crawford III), several projects were begun to
crowd-source data on such events. These include Fatal Encounters and U.S. Police Shootings Data at
Deadspin. Another project, the Facebook page "Killed by Police" (or web-page www.KilledbyPolice.net) tracks killings starting May 1, 2013. In 2015, CopCrisis used the KilledByPolice.net data to generate info-graphics about police killings. A project affiliated with
Black Lives Matter,
Mapping Police Violence, tracks killings starting January 1, 2013, and conducts analyses and visualizations examining rates of killings by police department, city, state, and national trends over time. The National Police Misconduct Reporting Project was started in 2009 by David Packman to collect daily reports of police misconduct and was taken over by the
Cato Institute. The institute ceased collecting data in July 2017 and re-purposed the project to focus on
qualified immunity, renaming the project "Unlawful Shield". The Puppycide Database Project collects information about police use of lethal force against animals, people killed while defending their animals from police, or killed unintentionally while police were trying to kill animals. ==Frequency==