Students whose plots to attack schools were stopped demonstrated the same types of troubled histories as those who carried out attacks. They were badly bullied, often suffered from depression with stress at home, and exhibited behavior that worried others, according to a new study by the U.S. Secret Service’s National Threat Assessment Center. It examined 67 thwarted school plots nationwide from 2006-2018 in K-12 schools.

In analyzing 100 students responsible for threats, researchers said all of the plots were serious planned attacks in which the plotters took some initial steps toward carrying them out. The informants who alerted authorities likely saved lives. “The findings demonstrate there are almost always intervention points available before a student resorts to violence,” said Dr. Lina Alathari, the center’s director in a statement.

Researchers hope schools use the information from this study, which follows up on a 2019 report, to be better equipped to deal with the warning signs and prevent attacks.

“The study found expelling students doesn't eliminate the risk,” said Steven Driscoll, one of the authors. Instead, the key is to address bullying, provide mental health support and assess the impact of stressors in the home. “No students should fall through the cracks.”

The largest number of thwarted plots, 11, came in 2017. Many of the attacks were planned for April, the same month as the Columbine High School attack in 1999. Most of the schools targeted were public high schools, and they were in 33 states, with 37% in suburban areas, and 14% in cities.

The plotters were overwhelmingly male. Only five were female. Most were motivated by grievances against them, usually peers and bullying. Many were suicidal or had depression. More than half had been impacted by adverse childhood experiences like substance abuse at home or parental mental health issues, and many had intended to kill themselves as part of the attack.

But most important, the researchers said, about 94% talked about their attacks and what they intended to do in some way, whether orally or electronically, and 75% were detected because the plotters talked about them. About 36% were thwarted within two days of their intended attacks.

“First and foremost, targeted violence is preventable if communities can identify warning signs and intervene,” Driscoll told the Associated Press. “The primary objective is providing a student with help as early as possible.”

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