The shooting spree in a Colorado cinema last month that killed 12 people and injured 58 has provoked many questions and much soul-searching. Some reports have even suggested that because the perpetrator, James Holmes, was until just weeks earlier a graduate student supported by a US National Institutes of Health (NIH) training grant, the biomedical agency is somehow implicated.

The insinuation is ludicrous, but the attention it received speaks volumes about the political reluctance in the United States to address the laws that made it possible for Holmes to obtain his arsenal of firearms. In this climate, discussions of the multiple murders sounded all too often like descriptions of the random and inevitable carnage caused by a tornado or an earthquake.

Natural disasters, truly unavoidable events, can be combated with science. The US Geological Survey, for instance, has some 250 employees dedicated to the assessment of earthquake hazards.

There is no such US government effort for research on firearms — the National Rifle Association has helped see to that. The lobby group that represents gun owners began to squash scientific efforts in 1996, when, using proxies in Congress, it shut down a fledgling, US$2.6-million gun-violence research effort by the US Centers for Disease Control and Prevention (CDC) in Atlanta, Georgia.

Among other things, that work revealed that people living in homes where there was a gun faced a 2.7-fold greater risk of homicide (A. L. Kellermann et al. N. Engl. J. Med. 329, 1084–1091; 1993) and a 4.8-fold greater risk of suicide (A. L. Kellermann et al. N. Engl. J. Med. 327, 467–472; 1992). Ever since, Congress has included in annual spending laws the stipulation that none of the CDC's injury-prevention funds “may be used to advocate or promote gun control”.

The gun lobby's reach grew still wider this year, when the ban was extended to all agencies in the Department of Health and Human Services, including, most prominently, the NIH. The agency, to its credit, has chosen to read the ban narrowly. “The NIH supports research and public health education programs on injury prevention and violence reduction,” it said in a statement. “This effort includes programs related to firearm violence, which is a public health concern.

Even so, the work that the NIH does support in this arena is limited. A search of the agency's grant database for the word 'firearm' returns just five projects, funded at a combined total of $2.6 million in 2011. One of these looks at the relationship between acute alcohol use and different methods of suicide, including the use of firearms. Another aims to create a training and education resource for families of children with traumatic brain injury.

Like any sound public policy, rational decisions on firearms cannot be born in a scientific vacuum. There is a desperate need for peer-reviewed research to address even basic questions, such as whether there is a way to use the registration and licensing of gun owners to reduce the associated fatalities — which totalled 31,347 in the United States in 2009, the most recent year for which data are available. It is incumbent on scientists and the public to insist to their law-makers that research on such rudimentary questions is not sacrificed on the altar of politics. If the politicians do not hear this message forcefully and regularly, the chilling effect of special interests on research into charged but crucial questions in any number of policy areas will only grow.