It seems that not a week passes without a new report of a mass shooting in the United States.

The gun epidemic, long simmering, has in the past few weeks seemed to reach a new phase in the public discourse.

The shootings in San Bernardino, California, occasioned a nearly unprecedented front-page editorial in The New York Times, the country’s “paper of record,” together with comments, once again, from the president, urging Congress to act on regulating firearms and firearm violence.

The top-level data on the problem are at this point familiar. There are about 32,000 gun deaths a year in the United States, approximately the same number as deaths from motor vehicle accidents.

The number of firearm deaths has been stable essentially since 2000. There are another 180,000 or so people injured by firearms annually in the country. These numbers far outstrip the consequences of firearms among our peer high-income countries, with stricter gun regulations.

What ails us? Why do we continue to accept these consequences of firearms when other countries do not?

The discussions in the public space over the past several weeks have illuminated some of these challenges, including a gun culture that is fueled by historical concern with individual rights to gun ownership, and an effective pro-gun lobby that aggressively penalizes legislators who aim to introduce basic gun control regulations.

I would suggest that one more factor that has held us back on this front is the relatively limited data we have available about firearms and firearm violence.

We don’t have enough data on gun violence

For example, there exists no national registry of victims of firearm violence, comparable to the registry we have to follow victims of the September 11, 2001, terrorist attacks, or to any number of other large-scale health threats. Our understanding of the consequences of gun violence is essentially limited to statistics on firearm deaths and injuries. That’s it.

APGun sales across the US spike after mass shootings.

While gun violence is a public health problem, it is not studied the same way other public health problems are.

That is because our national health organizations, principally the Centers for Disease Control and Prevention (CDC) and the National Institutes of Health (NIH), have avoided firearm-related research for almost 20 years.

Why doesn’t the federal government fund firearms research?

The roots of this challenge go back to 1996. Spurred by a 1993 article published in the New England Journal of Medicine about gun ownership as a risk factor for homicide, the National Rife Association suggested that the agency was advocating for gun control.

Because the CDC funded the research, the NRA pushed Congress, in a 1996 omnibus bill, to state:

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. The CDC broadly interpreted this as a bar on firearms research, with other federal funders following suit. This has had a chilling effect on gun research.

Ironically, the author of the amendment that cast this pall on firearm research, Congressman Jay Dickey, has since recanted, noting correctly in 2012 that “We won’t know the cause of gun violence until we look for it.”

We need good data to write good policy

Because of the bar on research, our understanding of the real consequences of the firearm epidemic is surface deep.

For example, while we know the number of deaths by gun and the number injured, we have no data about the psychological consequences of firearm violence, either among those injured or among their loved ones. We do not know who the corollary victims of gun violence are, or what the consequences are for this group.

REUTERS/Mike BlakePallbearers carry the casket of San Bernardino shooting victim Yvette Velasco during her memorial service in Covina, California, December 10, 2015.

We do not know the influence of common substances such as alcohol on the risk of firearm homicide or suicide. We do not know the real costs of firearm violence, including physical, mental and community harms linked to firearms.

And, centrally, we do not know the most effective policy levers that we can use to limit the gun violence epidemic simply because we have not done the research to understand the policy measures that can most effectively reduce or prevent gun violence.

This is precisely the kind of public health research that groups like the CDC and NIH fund for pressing public health problems, and should fund for firearm research.

Unfortunately, a shortage of data creates space for speculation, conjecture and ill-informed argument that threatens reasoned public discussion and progressive action on the issue.

Moving forward

There is hope on this issue. President Obama recently ordered the CDC to return to studying the causes of gun violence.

However, the executive action was not accompanied by the dedication of any new money to the issue, and until such funds are available, the CDC, like any other funder, would need to cut spending in some other area to sponsor this research.

APObama will push ahead with executive actions on gun control in 2016.

An omnibus spending bill put the funding ban in place, and an omnibus spending bill could also undo it. As Congress works toward a bill to fund the government, Democrats are pushing to lift the ban on gun violence research.

On December 10, House Minority Leader Nancy Pelosi said, “We must insist that we cannot have a bill leave the station that still has that ban on research in it.”

The United States has had enormous success in responding to other challenges to public health, including, for example, motor vehicle safety, through gathering data that understands the challenge and implementing structural changes to mitigate the potential harm.

On the issue of firearm violence, we are not even at the first step.