(CN) — A grocery store. School. Work. Public transit. Church. A nightclub. It’s impossible to predict where and when a mass attack may take place in America, but a report published by the National Threat Assessment Center on Wednesday found the people closest to an attacker often sense something is wrong.
“Significantly the study revealed that in most cases attackers exhibited behavior that elicited concern from family members, friends, neighbors, classmates, co-workers and others,” said U.S. Secret Service director Kimberly Cheatle said in a teleconference.
The National Threat Assessment Center is a branch of the Secret Service that has been studying mass attacks for more than 25 years.
“This means that communities and public safety agencies often have the opportunity to identify warning signs and intervene before violence has occurred,” Cheatle said. “The value of bystander reporting cannot be overstated.”
The report analyzed the backgrounds, motives and pre-attack behavior of 200 individuals who carried out 173 mass murders from 2016 to 2020, collectively killing 513 people and injuring 1,234. While the highest number of attackers were white men under the age of 44, reported attacks were carried out by both men and women of a diversity of races and ages ranging from 14 to 87.
Still the people in the lives of more than three-quarters of the attackers said they noticed changes in behavior leading up to the act of violence — from men who started or stopped shaving, to declines in work quality, increased aggression or the sudden onset of mellowness.
“Those around us are best poised to see when we might have a change in our behavior or demeanor,” said Meagan Cutler, a social scientist who worked on the study. “Being attuned to changes away from our normal is something to keep in mind.”
Although the highest number of bystanders who raised concerns about the attacker were direct family members, the report found friends, acquaintances and co-workers were also poised to notice and report worrisome changes in behavior.
“Targeted violence is preventable when communities are equipped with the appropriate tools, training and resources to intervene before violence occurs,” the report says. Behavioral threat assessment programs “are not designed to predict who will become violent, but rather to identify, assess and intervene with individuals who display threatening or other concerning behaviors that indicate they may pose a risk of harm to themselves or others.”
The service additionally identified several trends that applied to many of the mass murderers studied, including having a history of violence or mental illness and being exposed to stress. Researchers found the vast majority of the attackers experienced a stressful event during the year prior to the attack, ranging from issues with money to romantic relationships, court proceedings, personal health, work, mental health and homelessness.
Half of mass killers experienced a stressful event within 30 days of the attack, like being fired, kicked out of a business, or receiving a notice of eviction or foreclosure.
While investigators do not always uncover the motive behind an attack, the most commonly reported motive is retaliation for a perceived wrong, including personal, domestic and workplace grievances. Less than 10% of killers were motived by the outright desire to kill or to obtain notoriety.
Roughly 25% of attackers believed in or were motivated by hateful ideologies or conspiracies ranging from antisemitism, anti-LGBTQ+, anti-Asian or anti-white beliefs. Others harbored as antigovernment and antipolice views.
In light of balancing First Amendment rights, the agency recommended “directing resources, training and public messaging toward countering hate and other extremist belief systems that have been historically associated with violence.”
Most mass attacks are carried out with legally obtained and possessed weapons. Three-quarters of mass murderers used firearms, but attacks were also carried out with knives, vehicles, explosives and blunt objects.
While the report identified trends among individuals who committed acts of mass violence, most people who exhibit these behaviors day to day don’t actually plan or carry out attacks.
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