School Violence and Safety, Characteristics of

The horrific killings in December 2012 of 26 children and teachers at Sandy Hook Elementary School in Newtown, Connecticut, underscored once more the vulnerability of our nation’s schools and the need for local police to be prepared for such critical incidents. Although one study found that mass killings—defined as incidents in which four or more people are killed by the attacker—only account for about 1% of all murders, on average such incidents occur about every two weeks; children (ages 12 and under) are frequently victims, representing about one-fifth of all victims.

Much has changed since the April 1999 mass killings of 13 people by two shooters at Columbine High School in Littleton, Colorado, where on-scene officers waited 45 minutes for an elite SWAT team to arrive. ...