Here are preliminary findings from the Secret Service's study of 41 school shooters in 37 incidents.

The Secret Service shared the findings with the Sun-Times, without confidential information from the files. The Sun-Times selected quotations from public records to illustrate the findings.

PLANNING
They don't "snap." These attacks were neither spontaneous nor impulsive. In almost all cases, the attacker developed the idea in advance. Half considered the attack for at least two weeks and had a plan for at least two days.
Two years before the shootings at Columbine near Littleton, Colo., Dylan Klebold wrote in his journal, "I'll go on my killing spree against anyone I want."
One student showed his friends four bullets: three for people he hated and one for himself. And that's just how he used them.

CONCERN
Almost all attackers had come to the attention of someone (school officials, police, fellow students) for disturbing behavior. One student worried his friends by talking often of putting rat poison in the cheese shakers at a pizza restaurant. Others wrote poems about homicide and suicide.
Adults usually didn't investigate, remaining unaware of the depth of the problem. Few of the boys had close relationships with adults. Few participated in organized sports or other group activities.
Q. Where were the grown-ups?
A. Luke Woodham in Pearl, Miss., recalls, "Most of them didn't care. I just felt like nobody cared. I just wanted to hurt them or kill them."
Before Columbine, the local sheriff had been given copies of Eric Harris' Web site, describing his pipe bombs, with page after page of threats: "You all better f------ hide in your houses because im comin for EVERYONE soon, and I WILL be armed to the f------ teeth and I WILL shoot to kill and I WILL f------ KILL EVERYTHING."

School shooters don't just snap. They aren't loners. Few have mental illnesses. And other children who know what's coming often don't tell.
Photo by GARY CASKEY ©REUTERS 1999

COMMUNICATION
They aren't "loners." In more than three-fourths of the cases, the attacker told someone about his interest in mounting an attack at school. In more than half the incidents, the attacker told more than one person. Some people knew detailed information, while others knew "something spectacular" was going to happen on a particular date. These communications were usually with friends or schoolmates; in only two cases was the confidant an adult. In fewer than one-fourth of the cases did the attacker make a direct threat to the target.
"I'm going to kill her sometime today or tomorrow," a student warned.

BYSTANDERS
Those who knew in advance sometimes encouraged the attack and sometimes urged an escalation of the plan, but only rarely told anyone or shared their concern with others before the attack. In about one-third of the cases, the attack was influenced or dared by others or a group.
A friend of Harris' asked him what he was going to do with bomb-making equipment. "He said he was going to blow up the school."
A friend of one shooter was told what would happen. "I was his friend. Calling someone would have been a betrayal. It just didn't seem right to tell."

"Reprinted with special permission from the Chicago Sun-Times Inc. @2001"