The characteristics of gun violence in the U.S. are largely unknown because key federal health agencies have been banned from conducting such research since the mid-1990s.
President Obama, however, wants to change that.
In presenting his plan to reduce gun violence last month, Obama said he would order the Centers for Disease Control and Prevention to resume scientific studies of the issue.
"We don't benefit from ignorance," he said.
On Monday, however, the president acknowledged in a speech to the Minneapolis Police Department that he might be in for a fight. "Because for a long time, even looking at the evidence was considered somehow tough politics," he said.
Indeed, opponents on Capitol Hill are already making their concerns heard.
"Gun violence is not a disease," Iowa Senator Charles Grassley, the top Republican on the Senate Judiciary Committee, said in a recent speech on the Senate floor. "And lawful gun ownership is not a disease. It is a constitutionally protected, individual right."
But gun researchers say it is long past time that the research resumes.
"We really don't know some of the answers to the critical questions we need to know about [gun violence] in order to have more effective law enforcement and more effective public policy," says Harold Pollack, co-director of the Crime Lab at the University of Chicago.
At the lab, most research on things like underground gun markets and strategies to prevent gun violence has to be done with nonfederal funds. "There's been a chilling effect brought about [by] the constraints that the president spoke about and by the political history of this debate at CDC and elsewhere," Pollack says.
RAND Corp.'s Dr. Art Kellermann, a health policy analyst, is well-acquainted with the political history of the debate.
Kellermann grew up with guns in East Tennessee. "Having a gun in your house was about as controversial as having a washing machine," he says. He says he was quite familiar with the idea of keeping a gun in the house for protection.
"But as a young ER doc, I wasn't seeing too many bad guys shot by homeowners," he says. "I was seeing kids shot by another child while they played with a gun they had found. I saw spouses who had shot one or the other in a family dispute. And I saw older individuals and sometimes teenage kids who used a gun to either take their life or attempt to take their life."
So he and several other researchers set out to study what they saw as cost-benefit analyses of the dangers of keeping guns, particularly loaded guns, in the home.
The findings were all strikingly similar. "On the balance, the risks of a tragedy in the home — a homicide or suicide — were actually increased if a gun was kept there rather than not," he says.
Gun advocates blasted the research.
Michael Hammond, legislative counsel with the group Gun Owners of America, says it appeared as if the CDC "was going to ... basically issue politicized studies with taxpayer funding concerning the Second Amendment issues."
The group first tried to defund the agency's entire injury control center, though research on gun violence amounted to about $2.6 million of a $43 million budget.
The following year, a compromise of sorts was reached. Congressional funders took the $2.6 million the CDC had been spending on gun violence research and ordered that it be used instead to study traumatic brain injury.
It was very clever, says Rep. Rosa DeLauro, D-Conn., now the ranking member of the appropriations subcommittee that oversees the Department of Health and Human Services budget. "How do you say no to traumatic brain injury?"
But opponents of gun violence research also added language stipulating that "none of the funds made available for injury prevention and control at the Centers for Disease Control and Prevention may be used to advocate or promote gun control."
Obama says his order that the research resume is premised on the legal opinion that gun violence research isn't the same as advocating or promoting gun control.
That's what researchers have always claimed, too. Public health research, they say, is based on making things safer, not on taking them away.
"It's ironic if you think about it," says Kellermann. "The last 20 years we've made spectacular progress with car crashes ... in reducing drownings, smoke inhalation from house fires. And yet we've not banned matches, swimming pools or automobiles."
But neither the CDC nor researchers wanted to take a chance testing the limits of the research ban, says DeLauro, and that essentially shut the research down.
Lawmakers have since expanded the ban — today it covers not only research at the CDC but also other agencies at HHS, including the National Institutes of Health — and they even added anti-gun control language to the 2010 Affordable Care Act.
HHS Secretary Kathleen Sebelius said the department is "committed to re-engaging gun violence research" at CDC and NIH.
But the only real way to ensure the research restarts is for Congress to drop the existing language from the annual spending bill and restore funding.
A spokesman for Georgia Republican Rep. Jack Kingston, the new chairman of the HHS spending panel, said the chairman is planning to hold hearings on the matter. "If CDC can show they can do nonbiased and nonpolitically motivated studies, that's something he'd be interested in," the spokesman said.
But like everything else gun-related in Congress, nothing is guaranteed.
AUDIE CORNISH, HOST:
As part of his plan to reduce gun violence, President Obama has directed the federal Centers for Disease Control and Prevention to resume scientific studies of the issue. He's effectively ordering the end of a ban that's been in place for nearly two decades.
But as NPR's Julie Rovner reports, that's no simple task
JULIE ROVNER, BYLINE: Art Kellermann first began studying gun violence in the 1980s. As an emergency room doctor in Atlanta, he saw a lot of gun injuries he says weren't associated with bad guys. The results of his studies and those of other researchers at the time were strikingly similar, he says.
DR. ART KELLERMANN: On the balance, the risks of a tragedy in the home - a homicide or suicide - were actually increased if a gun was kept there rather than not.
ROVNER: Those studies were mostly funded by the CDC's Injury Prevention Center and published in some of the nation's most prestigious medical journals. But gun advocates hotly disputed the findings.
Michael Hammond, of the group Gun Owners of America, was involved in the effort to ban CDC from funding gun violence research back in 1996.
MICHAEL HAMMOND: CDC, it appeared, was going to basically issue politicized studies with tax-payer funding, concerning the Second Amendment issues. And at that point, a number of people thought that the last thing we needed was tax-payer funding of junk science.
ROVNER: The National Rifle Association, which didn't respond to repeated requests for comment for this story, all but declared war on the CDC in 1995. First, the NRA tried to defund the agency's entire Injury Control Center, even though the gun violence research amounted to only a small part of its portfolio.
Eventually, a compromise of sorts was reached.
REPRESENTATIVE ROSA DELAURO: They were clever at the time, as you may recall.
ROVNER: Connecticut Congresswoman Rosa DeLauro, is now the ranking Democrat on the subcommittee that sets the Department of Health and Human Services budget. She was a relatively junior member back then. DeLauro says congressional funders took the amount of money CDC was spending on gun violence research and ordered that it be used instead to study traumatic brain injury.
DELAURO: How do you say no to traumatic brain injury?
ROVNER: But gun violence research opponents also added something else to the spending bill that year and every year since - language saying none of the funds made available to the CDC could be used to, quote, "advocate or promote gun control."
Now, President Obama says his order that the research resume is premised on the legal opinion that gun violence research is not the same as advocating or promoting gun control. That's what researchers have always claimed, as well.
Kellermann says most public health research is based on making things safer, not taking them away.
KELLERMANN: It's ironic. If you think about it, the last 20 years we've made spectacular progress with car crashes, we've made spectacular progress in reducing drownings, smoke inhalation from house fires. And yet, we've not banned matches, swimming pools, or automobiles.
ROVNER: But over the years, it appears neither the CDC nor researchers wanted to take a chance testing the limits of the research ban, says Congresswoman DeLauro, which essentially shut the research down.
DELAURO: CDC didn't want to risk the agency; people didn't want to risk careers. So what is it? Fifteen, 17 years now since there's been any really solid data or research, you know, on injuries from gun violence?
ROVNER: Lawmakers have actually expanded the ban over the years to include other agencies, including the National Institutes of Health. Gun advocates even got language added to the all-Democratic 2010 Affordable Care Act.
Michael Hammond of the Gun Owners Association says he was personally involved in that. Among the things gun owners worried about was the possibility that insurers might impose a gun surcharge in the name of public health.
HAMMOND: And then that gun surcharge gradually climbs and climbs and climbs, until it is no longer financially feasible for most people to own guns.
ROVNER: Meanwhile, the president's order for CDC to resume research is getting some pushback in Congress. Here's Iowa Republican Charles Grassley on the Senate floor last week.
SENATOR CHARLES GRASSLEY REPUBLICAN, IOWA: Gun violence is not a disease. And lawful gun ownership is not a disease. It is a constitutionally protected, individual right.
ROVNER: Health and Human Services Secretary Kathleen Sebelius has said the department is, quote, "committed to re-engaging gun violence research at CDC and NIH."
But the only real way to ensure the research restarts is for Congress to drop the existing language from the annual spending bill and restore funding. Congresswoman DeLauro and other Democrats say they'll fight for that. Georgia Republican Jack Kingston, the new chairman of the House HHS spending panel, said through a spokesman he's willing to take a look. But like everything else gun-related in Congress, nothing is guaranteed.
Julie Rovner, NPR News, Washington. Transcript provided by NPR, Copyright NPR.