The spotty federal record is a result of a voluntary self-reporting system for local police departments that often refuse to send the data, the Guardian reported Thursday.
Of 18,000 law enforcement agencies in the United States, only 224 reported incidents of fatal shootings by officers in 2014, according to documents obtained by the British paper. The Guardian's own police killing tally project, "The Counted," indicates that police had already fatally shot 224 people by April 10 of this year. New York City, where officer Daniel Pantaleo kept Eric Garner in a chokehold until he died in broad daylight, reported data from just one year between 2004 and 2014.
"We have no way of knowing how many incidents may have been omitted," FBI spokesman Stephen Fischer told the Guardian. A separate Mic request for comment by Fischer was not answered.
It's not the first time that the authorities have been made aware of this problem. A 2014 review by the Wall Street Journal found that between 2007 and 2012, more than 550 police killings in the U.S. went unrecorded in federal statistics.
"When cops are killed, there is a very careful account and there's a national database," Jeffrey Fagan, a law professor at Columbia University told the Wall Street Journal. "Why not the other side of the ledger?"
Accurate reporting, however, is only part of the story. With police killings meticulously documented by websites like KilledByPolice.net and the Guardian's The Counted project, the lion's share of attention has focused on bringing down the numbers. While Eric Garner and Tamir Rice received worldwide attention, according to some estimates their deaths were only two of more than 1,000 caused by police in 2014.
During the Democrats' first presidential debate on Tuesday, the candidates were asked directly about a subject that has caused more than one of them significant discomfort on the campaign trail. The question, posed by a Facebook user, was, "Do black lives matter, or do all lives matter?" In a previous forum in July, former Maryland governor Martin O'Malley famously said that "all lives matter," a statement that was widely met with derision. He later apologized.
"Do black lives matter, or do all lives matter?"
Vermont senator Bernie Sanders, meanwhile, saw a campaign event in Seattle disrupted by protesters from the movement in August. Despite decades of well-documented civil rights activism, he, too, has been accused of not being responsive enough to the group's needs.
As of this writing, there have been at least 936 people killed by police in 2015.