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Definition: mass murder from The Macquarie Dictionary

the murder of a large number of people at the same time; multicide.

mass murderer noun


Summary Article: Mass Murder
from Encyclopedia of Interpersonal Violence

Mass murder is the killing of multiple people at one location in a relatively short period of time. It is commonly believed that the mass murderer is an individual who kills randomly after experiencing a mental breakdown or psychotic episode. Research, however, does not support this belief. Studies of mass murderers indicate that their motivations typically stem from some wrong they perceive has been unjustly inflicted upon them. Their hatred of the supposed wrongdoer festers over time until some incident prompts them to act out against the wrongdoer and/or others who belong to the wrongdoer’s group (e.g., women, coworkers). Consequently, criminologists delineate two types of mass murders. One type involves the killing of specific individuals whom the offender believes has wronged him or her. For example, in one recent mass murder, two students at Columbine High School in Colorado shot classmates whom they felt had ignored or mistreated them. The second type of mass murder involves killing individuals who have not had personal contact or a relationship with the offender, but who belong to a group the offender has come to hate. For example, in 1989, at the University of Montreal, a man who had been rejected from the school’s engineering program went into an engineering class, ordered all the men to leave, and then shot the women, killing 14 and wounding 13 because he believed that the need to admit more women to the program had led to his rejection. The research also shows that mass murderers usually think about committing murder for some time before they actually act and prepare for the crime (e.g., by stockpiling weapons), although they may not plan the exact time and location of the killings.

The mass murderer may kill multiple people at different locations over a period of days rather than in one location in a short time. This type of mass murder is usually referred to as spree murder. The characteristics of mass murderers and spree murderers, however, are largely indistinguishable. Most are White males, who are impulsive, alienated, depressed, and frustrated, largely because of their perception of having been unjustly wronged. They appear to be fascinated by guns and have the weapons at their disposal. The way they kill is very public, and they appear to be concerned about their own lives in the process. In fact, most commit suicide or die at the hands of police at or near the crime scene. An important exception to this general portrait, though, is felony-related and gang-related mass murders. In these types of murders, the offenders are usually young non-White men, who do not commit suicide and who are not killed by police at or near the crime scene.

Although mass murders are rare relative to other types of violent offenses, data show that they have increased in the United States in recent years. During the decade of the 1950s, for instance, there were only four mass murders. Throughout the 1960s, there were seven mass murders. However, from the mid-1970s to 1991, there were 269 cases that resulted in the deaths of 1,447 people. From 2000 to 2002 alone, there were 567 cases. This dramatic increase in only half a century is alarming, but criminologists disagree over why it has occurred. In contrast, mass murder is relatively rare outside the United States, leading some criminologists to argue that the relative ease of acquiring guns in the United States is, in large part, responsible for the relatively high rate of mass murders in this country.

    See also
  • Gang Violence; Homicides, Criminal; Serial Murder/Serial Killers

Further Readings
  • Fox, J.; Levin, J. (2001). The will to kill: Making sense of senseless murder. Boston: Allyn & Bacon.
  • Fox, J.; Levin, J. (2005). Extreme killing: Understanding serial and mass murder. Thousand Oaks, CA: Sage.
  • Holmes, R. M.; Holmes, S. J. Understanding mass murder: A starting point. Federal Probation, 56, (1992). 53-61.
  • Claire M. Renzetti
    Copyright © 2008 by SAGE Publications, Inc.

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