By Lois Beckett, ProPublica.
How many Americans have been shot over the past 10 years? No one really knows. We don’t even know if the number of people shot annually has gone up or down over that time.
The government’s own numbers seem to conflict. One source of data on shooting victims suggests that gun-related violence has been declining for years, while another government estimate actually shows an increase in the number of people who have been shot. Each estimate is based on limited, incomplete data. Not even the FBI tracks the total number of nonfatal gunshot wounds.
“We know how many people die, but not how many are injured and survive,” said Dr. Demetrios Demetriades, a Los Angeles trauma surgeon who has been studying nationwide gunshot injury trends.
While the number of gun murders has decreased in recent years, there’s debate over whether this reflects a drop in the total number of shootings, or an improvement in how many lives emergency room doctors can save.
Doctors and researchers have been advocating for better gun injury data since the late 1980s. But fierce political battles over gun violence research — including pressure from congressional Republicans that put an end to some government-funded studies on firearms — has meant that we still don’t know many basic facts about gun violence in America.
“In the absence of real data, politicians and policymakers do what the hell they want,” Dr. David Livingston, the director of the New Jersey Trauma Center at University Hospital in Newark. said “They do what the hell they want anyway,” he added, “but in the absence of data, they have nobody to call them on it.”
An initial push to create a national database of firearm injuries in the late 1980s and early 1990s was slowed by the political fight over Centers for Disease Control and Prevention funding for gun research, according to a history of the project written by researchers who worked on it. To make the effort more politically viable, as well as more scientifically rigorous, researchers decided to collect data on all violent deaths, not just firearm deaths.
And to cut costs, they decided to focus only on fatal injuries. Even that more limited effort has languished without full congressional funding — the database currently covers fewer than half of all states.
Most discussions of crime trends in America look back 20 years, to 1993, when violent crime of all kinds hit its peak. Compare 1993 to today, and the picture looks bright: The number of murders is down nearly 50 percent, and other kinds of violent crime have dropped even further.
The Department of Justice has estimates of nonfatal shootings that suggest a similar trend: Its National Crime Victimization Survey shows a decline, from an average of about 22,000 nonfatal shootings in 2002, to roughly 12,000 a year from 2007 to 2011, according to a Department of Justice statistician.
But over the same time period, CDC estimates show that the number of Americans coming to hospitals with nonfatal, violent gun injuries has actually gone up: from an estimated 37,321 nonfatal gunshot injuries in 2002 to 55,544 in 2011.
The contrast between the two estimates is hard to clear up, since each data source has serious limitations.
Experts say that household data-gathering efforts, like the National Crime Victimization Survey, likely miss the Americans who are most likely to be victims of gun violence.
Shooting victims are “disproportionately young men of color who are living unstable lives and often involved in underground markets or criminal activity, and this is a group that is incredibly difficult to survey,” said Philip Cook, a gun violence expert at Duke University. “A lot of them are in jail at any point in time, or if they’re not in jail, they have no stable address.”
Meanwhile, the CDC numbers are based on a representative sample of 63 hospitals nationwide, and the margin of error for each estimate is very large. The CDC’s best guess for the number of nonfatal intentional shootings in 2012 is somewhere between 27,000 and 91,000.
“Uncertainty in the estimates precludes definitive conclusions,” one group of medical researchers explained in a back-and-forth in a journal on internal medicine last year.