“Did the 1994 Federal Assault Weapons Ban Affect Mass Shootings? A Time Series Analysis,” a paper presented at the annual meeting of the American Society of Criminology by Ivan Birch (University of Texas at Dalls), Grant Duwe (Minnesota Department of Corrections), and Tomislav Victor Kovandzic (UT-Dallas)
Mass public shootings are defined in this paper as a shooting with 4 or more victims (not including the shooter) in a public location. By this definition, from 1980 to 2012 there were 117 mass public shootings in the United States, in which there were 922 total victims (724 killed and 198 wounded).
(Note that there is no commonly agreed upon definition of “mass public shooting.” A March 18, 2013 Congressional Research Service report, “Public Mass Shootings in the United States,” uses a slightly different definition: “These are incidents occurring in relatively public places, involving four or more deaths—not including the shooter(s)—and gunmen who select victims somewhat indiscriminately. The violence in these cases is not a means to an end—the gunmen do not pursue criminal profit or kill in the name of terrorist ideologies, for example.” By this definition, in the 30 years from 1983-2013, the CRS identified 78 incidents with 547 killed and 476 injured, for a total of 1,050 victims. Mother Jones magazine uses a different definition, Reddit another, and criminologist James Alan Fox still another.)
Unlike homicides in general, which disproportionately affect those engaged in criminal activity, the victims of mass public shootings are often guilty of nothing more than going about their daily lives in schools, shopping malls, religious services, and movie theaters. What the CRS calls the indiscriminate selection of victims makes these events particularly disturbing.
At the same time, the likelihood of being the victim of a mass public shooting is extremely low. Over the 33 years covered by Birch, Duwe, and Kovandzic, 22 people were killed and 6 were wounded per year on average. By comparison, over the same time period the FBI’s Uniform Crime Reporting Statistics show 625,917 victims of murder or nonnegligent manslaughter, an average of 18,967 per year (I generated these numbers using the handy FBI UCR table building tool).
Another way of looking at the rarity of death by mass public shooting is to consider data on the number of deaths by mechanism and intent from the National Vital Statistics Report from the Centers for Disease Control. Considering only “unintentional” deaths (excluding suicide and homicide) in 2010, 3,782 people drowned, 26,009 fell to their deaths, 33,041 died of poisoning, 6,165 suffocated, and 4,383 pedestrians died in motor vehicle crashes (Table 18, pp. 83-84). And these are not anywhere near the leading causes of death in the United States, which are heart disease and cancer (over 500,000 deaths each in 2010).
The world can be a dangerous place, but as I have previously written about the “culture of fear,” mass public shootings and AR-15 style rifles should probably not be the biggest concern for most people.
In any event, the authors argue that the “assault weapons” ban did not have an effect on the firearm homicide rate overall because AR-15 style rifles are not often used in homicides. Indeed, rifles of any kind are used in less than 3 percent of homicides (323 of 12,664 in 2011).
But AR-15 style rifles are used more often in mass public shootings than in homicides in general. They were used in 18 of 117 (15.4%) mass public shootings covered by this study, and accounted for 19% of all victims killed (140 of 724) and 100% of the wounded (198 of 198). Of 922 total victims in mass public shootings, 338 (37%) were killed or wounded by AR-15 style rifles.
So, in terms of mass public shootings, AR-15 style rifles are slightly more lethal and much more likely to wound than other weapons. But, in part due to their rarity, the authors conclude that Assault Weapons Ban of 1994-2004 did not have a significant effect on mass public shootings.
In a recent article in the academic journal Homicide Studies, “Mass Shootings in America: Moving Beyond Newtown,” James Alan Fox and Monica J. DeLateur conclude: “Eliminating the risk of mass murder would involve extreme steps that we are unable or unwilling to take—abolishing the Second Amendment, achieving full employment, restoring our sense of community, and rounding up anyone who looks or acts at all suspicious. Mass murder just may be a price we must pay for living in a society where personal freedom is so highly valued” (p. 141)