There has been a rash of heavily publicized mass shootings in recent years. But those incidents, while tragic, are a tiny sliver of America’s gun homicide problem. Mayors Against Illegal Guns, analyzing FBI data, found that fewer than 1 percent of homicide victims in 2010 were killed in incidents where four or more people died.
A Congressional Research Service (CRS) report from 2013 identified 78 “public mass shootings” between 1983 and 2012, which claimed 547 lives. For context, 11,622 people (more than 20 times the mass shooting toll over three decades) died in gun homicides in 2012 alone — and murder is, in general, on the decline, so that number was higher in the 1980s and ‘90s. “While tragic and shocking, public mass shootings account for few of the murders or non-negligent homicides related to firearms that occur annually in the United States,” CRS concluded.
Some analyses find that mass shootings are, contrary to popular perception, fairly stable over time. James Alan Fox, a criminologist at Northeastern University, has found that the number of mass shooting victims, perpetrators, and incidents didn’t change much from 1980 to 2014:
Fox uses a fairly straightforward definition of mass shootings as shootings in which at least four people die, and found no statistically significant increase in the number of such incidents or the number of total victims.
Other researchers, like Mother Jones’ Mark Follman and the Harvard School of Public Health’s Amy P. Cohen, Deborah Azrael, and Matthew Miller use a more restrictive definition, excluding killings related to domestic violence, drugs, or gangs. Using data Follman and Mother Jones compiled, the Harvard researchers concluded in 2014 that the amount of time between mass shootings has been declining:
Vox uses yet another definition, which is instances in which four or more people are shot, not necessarily killed. The data there doesn’t go back far enough to make firm conclusions about whether the rate is increasing or holding steady.
Determining the “right” definition in cases like this doesn’t matter much for the gun control debate. The best case for gun control is about suicide, not mass shootings. But the definition fight matters for the purpose of ideological proxy warfare. Declaring Fox or Cohen et al right has a certain political valence in the wider gun control debate. Fox’s analysis seems to rebut liberal concerns about an increasing rate of mass shootings; Cohen et al seem to confirm those concerns.
You see something similar in discussions around school shootings, wherein gun control skeptics are as eager to declare that gang-related shootings in school are not real school shootings as they are to embrace Fox’s definition in which gang-related mass shootings are real mass shootings — and vice versa for gun control supporters.