Walter Scott, Eric Garner, Michael Brown, and Tamir Rice are just a few of the thousands of people killed by law enforcement in the past 15 years.

Vox's Anand Katakam created an interactive map with data from Fatal Encounters, a nonprofit trying to build a national database of police killings. It shows some of the deaths by law enforcement since 2000:

A huge majority of the more than 5,600 deaths on the map are from gunshots, which is hardly surprising given that guns are so deadly compared to other tools used by police. There are also a lot of noticeable fatalities from vehicle crashes, stun guns, and asphyxiations. In some cases, people died from stab wounds, medical emergencies, and what's called "suicide by cop," when someone commits suicide by baiting a police officer into using deadly force.

The data is far from perfect. Some of it is incomplete, with details about a victim's race, age, and other factors sometimes missing. D. Brian Burghart, head of Fatal Encounters, estimates that his organization's collection of reports from the public, media, and FBI only captures about 35 percent of total police killings.

The FBI collects some of this data from local and state agencies, but as Vox's Dara Lind explained, it's very limited. Reporting homicides for participating agencies is mandatory, but reporting the circumstances of homicides is not. So we might know that thousands of people die in a certain state, but we won't always know why those homicides happened and whether they involved police.

Participation in these reporting programs is also voluntary, making the number of reported homicides at best a minimum of what's going on across the country.

This means that it's hard to gauge, based on this incomplete data set alone, whether these types of killings are becoming more common. But since all of the data we have is so flawed, the Fatal Encounters database is perhaps the best context we have for the wide range of police use of force — especially as the issue continues to capture national attention in the aftermath of Scott, Garner, Brown, and Rice's deaths.

Watch: Why police are rarely prosecuted for shootings

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