There have been at least 69 in the last three decades - and most of the killers got their guns legally.
By - Mark Follman, Gavin Aronsen, and Deanna Pan - Updated: May 24, 2014, 10:45 PM EDT
It is perhaps too easy to forget how many times this has happened. The horrific mass murder at a movie theater in Colorado in July 2012, another at a Sikh temple in Wisconsin that August, another at a manufacturer in Minneapolis that Septemberβand then the unthinkable nightmare at a Connecticut elementary school that Decemberβwere some of the latest in an epidemic of such gun violence over the last three decades. Since 1982, there have been at least 69 mass shootings across the country, with the killings unfolding in 30 states from Massachusetts to Hawaii. Thirty-two of these mass shootings have occurred since 2006. Seven of them took place in 2012, and another five occurred in 2013, including in Santa Monica, California, and at the Washington Navy Yard. The first five months of 2014 brought major gun rampages at Fort Hood and in northern and southern California.
We've gathered detailed data on more than three decades of cases and mapped them below, including information on the shooters' profiles, the types of weapons they used, and the number of victims they injured and killed. The below analysis covers the cases from 1982 through 2012, and the map and database have been updated with cases through 2013.*
Weapons: Of the 143 guns possessed by the killers, more than three quarters were obtained legally. The arsenal included dozens of assault weapons and semi-automatic handguns with high-capacity magazines. (See charts below.) Just as Jeffrey Weise used a .40-caliber Glock to slaughter students in Red Lake, Minnesota, in 2005, so too did James Holmes, along with an AR-15 assault rifle, when blasting away at his victims in a darkened movie theater. In Newtown, Connecticut, Adam Lanza wielded a .223 Bushmaster semi-automatic assault rifle as he massacred 20 school children and six adults.
The killers: More than half of the cases involved school or workplace shootings (12 and 20, respectively); the other 30 cases took place in locations including shopping malls, restaurants, and religious and government buildings. Continued.