School shooting is a topic of intense interest in the United States. Though companies like MOSAIC Threat Assessment Systems sell products and services designed to identify potential threats, a thorough study of all United States school shootings by the U.S. Secret Service warned against the belief that a certain "type" of student would be a perpetrator. Any profile would fit too many students to be useful and may not apply to a potential perpetrator. Some lived with both parents in "an ideal, All-American family." Some were children of divorce, or lived in foster homes. A few were loners, but most had close friends. Some experts such as Alan Lipman have warned against the dearth of empirical validity of profiling methods.
While it may be simplistic to assume a straightforward "profile", the study did find certain similarities among the perpetrators. "The researchers found that killers do not 'snap'. They plan. They acquire weapons. These children take a long, considered, public path toward violence." Princeton's Katherine Newman has found that, far from being "loners", the perpetrators are "joiners" whose attempts at social integration fail, and that they let their thinking and even their plans be known, sometimes frequently over long periods of time.
Many of the shooters told Secret Service investigators that alienation or persecution drove them to violence. According to the United States Secret Service, (see Fein, R.A., Vossekuil, B., Pollack, W., Borum, R., Reddy, M.,& Modzeleski, W. Threat assessment in schools: A guide to managing threatening situations and creating safe school climates. U.S. Department of Education and U.S. Secret Service, May, 2002 for the research and the recommendations therefrom), instead of looking for traits, the Secret Service urges adults to ask about behavior:
1. What has this child said?
2. Do they have grievances?
3. What do their friends know?
4. Do they have access to weapons?
5. Are they depressed or despondent?
One "trait" that has not yet attracted as much attention is the gender difference: nearly all school shootings are perpetrated by young males, and in some instances the violence has clearly been gender-specific. Bob Herbert addressed this in an October 2006 New York Times editorial. Only two female school shooting incidents have been documented.
Another reported similarity is that most of the perpetrators had been taking antidepressant drugs, which have a documented history of producing violence and aggression as a side effect.
School shootings receive extensive media coverage and are infrequent. They have sometimes resulted in nationwide changes of schools' policies concerning discipline and security. Some experts have described fears about school shootings as a type of moral panic.
Such incidents may also lead to nationwide discussion on gun laws.