At the moment that Daniel was shot, I had just fallen asleep after a night on call in the cardiac intensive care unit. My attending during that rotation was Robert Gerszten, who offered us insights from the burgeoning field of metabolomics and cardiovascular disease: that alterations in levels of blood metabolites may precede chronic illnesses by decades — knowledge that might someday enable us to identify people at risk for diseases years before the first clinical manifestation. Contemplating the possibilities of this concept, caring for critically sick patients, and studying the vast cardiology literature, I found my mind filled with a complex amalgam of thoughts that often made post-call sleep restless.

Meanwhile, 150 miles away, the day had started like any Friday. My cousin Mark walked his oldest son to the bus stop at the end of the driveway. James always left for school first, and on that December day, it was still dark. At the sound of flip-flops on asphalt, Mark and James turned to see 7-year-old Daniel bounding toward them in his pajamas; he had woken up early and sprinted outside to see his older brother off to school. Then Daniel and Mark snuggled on the couch, played foosball in the basement and then “Jingle Bells” on the piano. At 8:30, it was Daniel's turn to trek down the driveway. Mark remembers holding Daniel's little hand for the whole walk to the yellow school bus that took his youngest son to Sandy Hook Elementary School.

The next week is a blur. There was waking up in a post-call haze to a phone tree that connected me in Boston to my parents in Florida to my aunt in Philadelphia to my uncle in Minneapolis — all trying to piece together incomplete snippets. Then the 6 p.m. call confirming that Daniel was dead. Then the Alison Krauss song that played as his little white casket came down the church aisle, and the firefighters who formed an honor guard because someone had heard that Daniel wanted to be a firefighter when he grew up. We walked out of the funeral, past hundreds of people lined up outside waiting to begin another child's funeral. There was driving home and going back to work. There was a residency program that supported me like family.

There were months of looking at pictures of Daniel every day and then a year of reading every book, every study, all the data I could find on firearm-violence prevention. There was a nation united by visceral pain, and for a while there seemed to be a demand for change. There came a return of normalcy in my life as a resident. Then there was a softening of that national resolve and a Senate vote against expanding background checks before firearm purchases. There was the first anniversary and what should have been Daniel's eighth and then ninth birthdays. There was the near-derailing of a Surgeon General nominee by the National Rifle Association (NRA). There were 96 more incidents of firearm violence on school campuses.1 And now here we are, beyond the second anniversary of Sandy Hook, long past time to cut through the shallow rhetoric that masquerades as a discussion about firearms in America.

When Dr. Gerszten works in his laboratory at Massachusetts General Hospital, he relies on an established scientific framework: understand the scope of the clinical problem, formulate a question, develop an approach to answering it, determine whether that answer provides a target for intervention. In his case, the scope of the problem is clear: heart disease is the number one killer of Americans, and although interventions and medications have reduced mortality, much about the pathophysiology of the disease remains poorly understood. Why do some people have heart attacks while others with similar habits don't? Gerszten's team works to identify metabolites in the blood that are markers of disease activity. Investigation of these pathways offers insights into disease progression and might ultimately provide targets for therapeutic intervention. Dozens of U.S. researchers, funded by the National Institutes of Health and the American Heart Association, are exploring these questions.

A similarly scientific, evidence-based approach can be adopted in the effort to reduce morbidity and mortality from firearms. Both the problem's scope and its relevance to physicians and patients are indisputable: in the United States, 30,000 people die each year from firearm injuries, according to the Centers for Disease Control and Prevention (CDC). Firearm injuries send 20 children and adolescents to the hospital every day2; every year, 2000 people receive gunshot-related spinal cord injuries and become lifelong patients.3 And this is an American problem: U.S. children 5 to 14 years of age are nearly 11 times as likely to be killed by a gun as their counterparts in other industrialized countries.4 By any rational definition, gun violence is a health issue, and physicians can take the lead on treating that as an apolitical fact.

Once we shift the issue of firearm-related morbidity and mortality from the political to the academic sphere, research questions can be formulated to address areas of uncertainty. And there are many. How many guns are there in the United States? Where and how are they stored? What percentage of homicide perpetrators could have passed a background check the day before the killing? When I posed these questions to David Hemenway, an injury-prevention researcher at the Harvard School of Public Health, he said, “We just don't know.”

How can we lack data regarding these basic, answerable questions? The story behind the suppression of firearm-injury prevention research is well known.5 In the 1980s and 1990s, CDC-supported research showed that the presence of a firearm in the home was associated with increased risks of suicide and homicide. In response, the NRA lobbied Congress to stop this line of investigation. Congress complied and in 1996 passed a budget appropriation stating that no CDC funds “may be used to advocate or promote gun control.” “Precisely what was or was not permitted under the clause was unclear,” according to injury-prevention researchers Kellermann and Rivara. “But no federal employee was willing to risk his or her career or the agency's funding to find out.”5 By 2011, this prohibition extended to all funding from the National Institutes of Health.

So federally funded research on firearm-injury prevention wilted, and many researchers involved in this work turned to other fields. Today, Hemenway estimates that 5 to 10 U.S. researchers are working full-time in this field. The pipeline of young researchers learning their methods is even less promising. Hemenway doesn't encourage his students to pursue a research career in the field, citing formidable hurdles: “There is no funding; the research is hard to do, and for the research that is done there is little publicity and few citations because the field is tiny.” Some of his center's funding for investigating suicide prevention comes from the Veterans Health Administration; the rest of his research on firearm-related injury depends on grants from foundations. In January 2013, President Barack Obama signed an executive order to lift the ban on CDC-funded research, but 2 years later, Hemenway says that no reliable funding source has been established. The lack of data and a research pipeline should be anathema not only to doctors in urban centers who bear witness to gun violence every day but also to physicians who own guns and understand their safe and respectful use. Acknowledging a need for research is not a commitment to enact any particular policy or to agree on an interpretation of the Second Amendment. Rather, it reflects the principle that high-quality data can inform better decisions and improve health.

When Daniel was gunned down while hiding in a bathroom with his first-grade classmates, my understanding of the pain wrought by firearm violence shifted from a theoretical concept that all doctors on some level understand to a haunting personal reality. As a hurting cousin and as a determined physician, I believe there is a path to better understanding and to reducing firearm-related violence. Armed with rigorously gathered data, we can elucidate pathways, identify targets, and develop interventions that may prevent other families from becoming part of a growing group whose lives have been transformed by gun violence — what my cousin Mark calls “the awful, painful club we never wanted to join and would do anything to quit if we could.”