Researchers studied 163 mass shootings. Here are the four things shooters have in common.

In an effort to understand the problem of mass shootings, the National Institute of Justice has helped fund a study to see what, if any, similarities exist between the perpetrators of these tragedies by looking at the data.

Researchers created a list of every shooting since 1966 where four or more people died, starting with the University of Texas Tower shooting.

The Violence Project founder James Densley says they were able to interview a number of shooters who are still alive and in prison, as well as their close relatives, law enforcement and victims.

He says that though not all the shooters were alike, their research did reveal four commonalities among the perpetrators.

A troubled or traumatic childhood

Densley told KXAN that the shooters they studied have “experienced trauma, abuse, and are living in very difficult circumstances.”

He says that things like abuse, neglect, or the suicide of a parent were all part of the common theme of the shooters.

Crisis point

The next commonality Densley says researchers found is that the person reached an identifiable point of crisis.

Some examples, Densley and fellow researcher Jillian Peterson told the LA Times, include some sort of grievance or rejection that triggers the shooters.

“Such crises were, in many cases, communicated to others through a marked change in behavior, an expression of suicidal thoughts or plans, or specific threats of violence,” they say.

“They’re often searching for answers to make sense of their life some way, to give it meaning,” Densley later told KXAN.

Validation in violence

Densley and his team found most shooters were fascinated with others who carried out similar acts. Researchers discovered one of the things that draws these individuals to commit these acts is notoriety they can attain.

They also go looking for the validation of their viewpoints, too, the study found.

Densley says people in crisis have always existed, but the means of communication and 24-hour news cycle haven’t.

“In the darkest corners of the internet, you can find anyone and everyone who will agree with your viewpoint,” he says.

It is here and in other places that their grief and thinking can seem legitimate, which “can create almost like a radicalization process where people start to believe that a mass shooting is a viable solution to their problems.”

Accessibility

Lastly, Densley says his team identified access to people, places and guns as something shooters have in common.

In 80% of school shootings, The Violence Project found the weapons used by the perpetrators were obtained from a family member.

In the majority of others, the shooters purchased the guns legally.

Having this understanding, Densley says, it’s clear there are opportunities to intervene.

“You can intervene in early childhood, you can intervene at the point of the crisis itself, you can intervene in the way of which we spread the message of hate,” Densley says. “We can also do things to prevent vulnerable individuals from getting access to firearms.”

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