“Half of all mass killings in the United States have occurred since the assault weapons ban expired in 2005, half of all of them in the history of the country.”
— Former president Bill Clinton, at the Consumer Electronics Show in Las Vegas, Jan. 9, 2013
A colleague spotted this eye-popping statistic by the former president and wondered if it was correct.
President Clinton signed the assault weapons ban into law in 1994, but it expired after 10 years and was not renewed. Even supporters have said it was riddled with loopholes, limiting its effectiveness. But the rash of mass shootings in recent years, including the Newtown tragedy, have provided new impetus for a renewed ban.
So let’s dig into the data and see what we find.
With gun shootings, you immediately get into some definitional issues. Depending on how one defines a “mass public shooting,” the answers might turn out to be different. There is also surprisingly little historical data about mass murder in the United States to go back all the way to the nation’s founding.
Grant Duwe, director of research and evaluation at the Minnesota Department of Corrections, assembled a data set going back 100 years for a 2007 book titled, “Mass Murder in the United States: A History.” He used the FBI Supplementary Homicide Reports, which date from 1976, and then supplemented the FBI reports with news reports (principally The New York Times) dating from 1900.
Duwe says the Times turned out to be a relatively reliable guide for mass murders across the country, since much of the post-1976 information also turned up in the contemporaneous FBI reports. As far as he knows, he is the only person who has assembled such a historical data set.
According to his research, he has identified 156 mass public shootings in the United States in the past 100 years.
Duwe defines a mass public shooting as an incident in which four or more victims are killed publicly with guns within 24 hours — in the workplace, schools, restaurants and other public places — excluding shootings in connection with crimes such as robbery, drugs or gangs. (Note that this would exclude a number of “mass murders” that sometimes get lumped into the data, such as the Beltway sniper who killed 10 people over a three-week period in 2002.)
Since 2005, when the assault ban expired, there have been 32 such mass public shootings, including seven in 2012, Duwe said. So that’s just over 20 percent of all mass public shootings, which is much less than Clinton’s 50 percent.
Here’s a breakdown per decade of Duwe’s data. It is important to note that these are raw figures; the United States had far fewer people 50 or 100 years ago.