In April 2000, marking the first anniversary of the Columbine tragedy, The New York Times published a series about violence that was based on one hundred cases of American rampage killers from the past fifty years. They noted that the incident in Littleton, Colorado was one of thirteen for the year 1999.
Rampage killers tend to be better educated than typical murderers, are likely to have military experience, and are more likely to kill themselves. The most significant influence on their outbursts appears to have been some form of mental illness. One-third had histories of violence and half had made threats. Most attacks were the result of a build-up over time of rage and the effects of depression, and more than half were able to purchase guns easily. "These are not impulsive acts," says J. Reid Meloy, a forensic psychologist and expert on sociopathic behavior. "There's a planning and a purpose, and an emotional detachment that's very long-term."
Of the 100 cases, nineteen were teenagers, and they showed a pattern that set them apart from the adults:
In forty cases of school violence in the past twenty years, the Secret Service's National Threat Assessment found that teenagers often told someone before they did the deed. Most of these kids were white and they preferred (and somehow acquired) semiautomatics. Almost half had shown some evidence of mental disturbance, including delusions and hallucinations.
School officials want to know if there are any clear signs to watch for and to tell parents about. They know they must be especially careful because any action they take has the potential of landing them in court. The problem is that few school psychologists have received training on this issue, so they're not sure what to do or what to look for. As with all dangerousness assessments, the most telling factor in what a child might do is what a child has already done. In other words, a history of violent actions or words is the best indicator of future violence potential.
Any pattern of behavior that persists over time tends to intensify. This does not necessarily mean that a bully will become a school killer, but it means that kids who develop an obsession with weapons or violent games, and who tend to threaten violence are more likely to eventually act out than those who don't. Some of the behaviors to be especially concerned about include an increase in:



