FBI agents told Georgia law enforcement leaders during a training session last week how to identify likely "active shooters" ahead of time and potentially stop a deadly attack.
Shooters often have suffered a loss or humiliation, and they plan for a violent resolution, the agents said. They may stop taking anti-depressants, alcohol or drugs in an effort to purify themselves before an attack.
They practice firing at a gun range. They may leave messages — called legacy tokens — on Facebook, YouTube or the comment sections of online news articles, explaining or foreshadowing their actions.
The man who brought 500 rounds of ammunition and an AK-47-style weapon to Ronald E. McNair Discovery Learning Academy in Decatur Tuesday didn't hurt anyone after a bookkeeper talked him down, but ideally he never would have walked into the school in the first place.
The key, FBI supervisory special agent Ray Johnson said, is for family members, acquaintances and school teachers of unstable individuals to call police or social services for help before a would-be shooter decides to move forward with his plot. Police usually aren't able to find out about such people on their own.
"Many active shooters display observable pre-attack behaviors which, if recognized, can lead to the disruption of a planned attack," said Johnson, coordinator of the National Center for the Analysis of Violent Crime in Atlanta's FBI office.
There's no demographic profile of what an active shooter looks like, he said. They range in age from 16 to 62, with an average age of 28, and they come from different races.
But they show similarities in their demeanor before launching shootings at schools or theaters, such as those in Newtown, Conn., Aurora, Colo., or Columbine, Colo.
Those who are closest to potential shooters are in the best position to decide whether something is seriously wrong, Johnson said. For example, they can tell if someone is eerily calm after an argument they'd normally be angry about, or they may notice if someone who usually drinks alcohol inexplicably stops.
"It's a holistic type thing. If it feels funny and looks funny, you have to do a contextual analysis of it," he said.
Mass shooters may have struggled with a life change or depression, and they've built up the resolve to kill others or themselves. Forty percent of the time they kill themselves, according to the FBI.
"These people usually don't wake up one morning and say they're going to do a mass shooting," said Sean Ragan, assistant special agent in charge of the Atlanta FBI office. "There's usually a series of events in their lives that might lead up to it."
The training of about 200 police chiefs, sheriffs and emergency responders at the Wednesday meeting in Canton was the third session in Georgia so far this year in the wake of the Sandy Hook Elementary School shooting in Newtown, Conn.
All 56 FBI field offices in the nation are holding two-day conferences for law enforcement managers about best practices and lessons learned from previous shootings.
"In this crazy world we live in, we have to train and take advantage of every resource available," Cherokee County Sheriff Roger Garrison said. "We've got to work together."
Information from: The Atlanta Journal-Constitution, http://www.ajc.com
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