摘要
Mass murders are horrific tragedies that gain intense media coverage; they do not seem rare any more. In the U.S., there have averaged 20 mass rampages a year since 1976. Of all killers, in general, only a modest percentage (5%–10%) are psychotic; however, among rampage mass murderers, a substantial percentage are likely psychotic since they often kill in numbers under bizarre circumstances, slaughtering innocent victims, including children. Although psychotic rampage murderers often kill at random, their mental health professionals, their families, and their friends are at high risk for violence, even homicide. Psychotic killers differ substantially from non-psychotic killers, but there are complex and overlapping motivations involving terrorism, anger, revenge, intoxication, and a desire for notoriety, all of which can be tinged with varying degrees of psychosis and challenge diagnostic categorizations. Of the 1,400 incidents of rampage murders found in the literature, 23 were selected for discussion within this article. Four of these 23 cases were motivated by terrorism, four were primarily motivated by anger and/or revenge, and 15 resulted from psychotic, delusional thinking. There is overlap in event characteristics and among motives in several of these cases. Prevention must be the primary goal. It is unlikely that gun control alone will be effective. Since nearly 50% of psychotic mass murderers had some contact with a mental health professional prior to their rampages, more effective methods of intervention may be possible, focusing on behavioral threat assessment and risk mitigation. An appreciation of how psychotic perpetrators differ from non-psychotic killers and their characteristics may contribute.