A report analyzing nearly 1,000 fatal police shootings that happened in 2015 claims evidence of racial bias. Researchers hope the study will strengthen a call for a national database on police use of force.
Federal data documenting fatal police shootings of suspects are notoriously hazy.
In 2015, FBI Director James Comey acknowledged as much -- while speaking to students at Georgetown University.
"How can we address concerns about officer-involved shootings, if we do not have a reliable grasp on the demographic and the circumstances of those incidences?" Comey said.
Justin Nix, who studies criminal justice at the University of Louisville, said the data are hazy because it isn't mandatory for law enforcement to report to the FBI when an officer kills a suspect.
"When using those data -- you're not working with all of the puzzle pieces," Nix said.
That inspired Nix and his team to turn to another data set: one documenting nearly 1,000 fatal police shootings, which was collected by the Washington Post. The paper won a Pulitzer Prize for its work.
Nix says the Post's data is the most complete out there. His team took it and analyzed it -- controlling for things like age, mental illness, and the threat level posed by the suspect.
"We found that black suspects who were shot and killed were twice as likely as white suspects to have been unarmed when they were fatally shot," Nix said.
Don Sawyer, an assistant professor of sociology at Quinnipiac University, said it's really hard to do research on officer-involved shootings, because of the lack of data.
"I think it's an important piece to push us to get our officials and police departments to start to release this information," Sawyer said.
Last year, the FBI said it would work on getting police to report more data on officer-involved shootings -- including the unknown number of non-fatal police shootings, which Justin Nix said his team couldn't account for, because the data simply don't exist.