While we have clear data on murders from gun violence, no one seems to know how many Americans are shot – and survive – every year. In fact, the government’s own numbers seem to conflict on the matter.

How can this be? And why has no one tried to resolve the difference?

ProPublica’s Lois Beckett explains that doctors and researchers have been pushing for clear numbers on gun injuries since 1989. “But what’s happened over that time is the politics of gun research, the politics of guns in America, are so divided and so fierce that even the effort to count the number of people injured by guns is incredibly political,” she says.

The CDC learned this lesson the hard way back in the mid-90s when it began funding more studies of firearm injuries – including a small study that found it was more dangerous to have a gun in the home for self-protection than it was to not have a gun at all.

Gun rights advocates believed this study – and other public health research on guns – was “laying the groundwork for the government to take away Americans’ second amendment rights, take away their guns. And that one study, and the fear that that was what research was doing, ended up torpedoing a lot of other CDC efforts,” Beckett says, including its early attempts to measure firearm injuries.

In 1996, Congress restricted the CDC from funding any research advocating gun control – an interesting measure since CDC researchers can't use their funding to advocate or lobby in general, Beckett notes.

Congress even tried to take $2.6 million of the CDC’s budget away – sending a clear political message to the CDC that conducting gun research comes at a high price. Gun violence research had essentially become the “political third rail.”

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