Daily Mail Online "After school shootings, I'm often asked 'what is the profile of school shooter?'
"It's human nature to want to understand why bad things happen – in large part so we can figure out how to avoid them in the future.
"With over 20 years of experience studying school shootings, interviewing shooters in prison, and managing thousands of active threat cases, here's what I can tell you about school shooters in the U.S.
Author Marisa Randazzo, Ph.D. is the former chief research psychologist for the U.S. Secret Service
"There was no accurate or useful profile of a school shooter – meaning no common demographic or external characteristics that described all or most of the school shooters.
"This information comes from research conducted primarily by the U.S. Secret Service and FBI.
"However, the behavior of school shooters is very similar and it suggests that many of these killers can be stopped before they decide to attack.
"Here's how:
"First, most school shooters planned their attacks in advance - sometimes for weeks, months, or even years before actually carrying out the shooting.
"Their behavior followed a similar progression: (i) they came up with an idea to do harm, (ii) they planned it out in more detail (sometimes researching previous school shootings for guidance or inspiration), (iii) they prepared for the attack, meaning they got the weapon(s) and other gear they intended to use to do harm, and (iv) they carried out the shooting.
"In the field of behavioral threat assessment, we refer to this behavioral progression as the 'pathway to violence.'" . . .
Marisa Randazzo, Ph.D. is the former chief research psychologist for the U.S. Secret Service and Executive Director for the Ontic Center of Excellence, which specializes in threat assessment & threat management