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Note: Varies by jurisdiction
Note: Varies by jurisdiction
|By victim or victims|
Mass murder (sometimes interchangeable with "mass destruction") is the act of murdering many people, typically simultaneously or over a relatively short period of time. The FBI defines mass murder as murdering four or more persons during an event with no "cooling-off period" between the murders. A mass murder typically occurs in a single location where one or more people kill several others. Many acts of mass murder end with the perpetrator(s) dying by suicide or suicide by cop.
A mass murder may be committed by individuals or organizations whereas a spree killing is committed by one or two individuals. Mass murderers differ from spree killers, who kill at two or more locations with almost no time break between murders and are not defined by the number of victims, and serial killers, who may kill people over long periods of time. Mass murder is the hypernym of genocide, which requires additional criteria.
Mass murder may also be defined as the intentional and indiscriminate murder of a large number of people by government agents; for example, shooting unarmed protestors, lobbing grenades into prison cells, and randomly executing civilians. The largest mass killings in history have been governmental attempts to exterminate entire groups or communities of people, often on the basis of ethnicity or religion. Some of these mass murders have been found to be genocides and others to be crimes against humanity, but often such crimes have led to few or no convictions of any type.
Mass murder by a state
The concept of state-sponsored mass murder covers a range of potential killings. It is defined as the intentional and indiscriminate murder of a large number of people by government agents. Examples are shooting of unarmed protestors, lobbing of grenades into prison cells, and random execution of civilians. Other examples of state-sponsored mass murder include:
- Deliberate massacres of captives or civilians during wartime by the state's military forces, such as these committed by Genghiz Khan, the Golden Horde, the troops of Vlad the Impaler, the Empire of Japan, the Soviet Union, and Nazi Germany during the Second Sino-Japanese War and World War II: the Nanjing Massacre, the Katyn Forest Massacre of Polish citizens in 1940 and the massacres of political prisoners after the launch of Operation Barbarossa, the Three Alls Policy, the massacre of Soviet Jews at Babi Yar, the mass murder of the Hungarian and German population in Vojvodina in the "Vengeance of Bacska, the murder of 24 unarmed villagers by British troops in the Batang Kali massacre during the Malayan Emergency, the murder of Vietnamese civilians by American soldiers in the My Lai Massacre during the Vietnam War, and in recent times, the hotly disputed, mass murder of civilian Sri Lankan Lee Tamils, by way of tactical shelling, by the Sri Lankan army during the Sri Lankan Civil War.
- Actions in which the state caused the death of large numbers of people, which political scientist R. J. Rummel calls "democide", which, in addition to the cases above, may include man-made disasters caused by the state, such as the Holodomor in the Soviet Union, the Khmer Rouge years in Cambodia, the mass killings in Indonesia during Suharto's rise to power, and the famines and poverty caused by the Great Leap Forward and the Cultural Revolution in the People's Republic of China.
Mass murder by individuals
Mass murderers may fall into any of a number of categories, including killers of family, of coworkers, of students, and of random strangers. Their motives for murder vary. A notable motivation for mass murder is revenge, but other motivations are possible, including the need for attention or fame.
Examples of mass murderers include King Dipendra of Nepal, Anders Behring Breivik, Timothy McVeigh, Adam Lanza, Cho Seung-Hui, Eric Harris, Dylan Klebold, William Unek, Campo Elías Delgado, Jeff Weise, Woo Bum-kon, Martin Bryant, Ahmed Ibragimov, Baruch Goldstein, Robert Bales, Omar Thornton, Nidal Malik Hasan, James Holmes, Andreas Lubitz  and Elliot Rodger.
Acting on the orders of Joseph Stalin, Vasili Blokhin's war crime killing of 7,000 Polish prisoners of war, shot in 28 days, is notable as one of the most organized and protracted mass murders by a single individual on record.
Police response and countermeasures
Analysis of the Columbine High School massacre and other incidents where first responders waited for backup has resulted in changed recommendations regarding what bystanders and first responders should do. Average response time by police to a mass shooting is typically much longer than the time the shooter is engaged in killing. While immediate action may be extremely dangerous, it may save lives which would be lost if people involved in the situation remain passive, or a police response is delayed until overwhelming force can be deployed. It is recommended that civilians involved in the incident take active steps to flee, hide, or fight the shooter and that individual law enforcement officers present or first arriving at the scene attempt immediately to engage the shooter. In many instances immediate action by civilians or law enforcement has saved lives.
Criticism of the analytical category "mass murder"
Commentators have pointed out that there are a wide variety of ways that homicides with more than several victims might be classified. Such incidents can be, and have been even in recent decades, classified many different ways including "as a mass shooting; as a school shooting; as mass murder; as workplace violence...; as a crime involving an assault rifle; as a case of a mentally ill person committing acts of violence; and so on."
How such rarely occurring incidents of homicide are classified tends to change significantly with time. "In the 1960s and 1970s,... it was understood that the key feature of [a number of such] cases was a high body count. These early discussions of mass murder lumped together [a variety of] cases that varied along what would come to be seen as important dimensions:
- Time: Did the killings occur more or less simultaneously, or did they extend over several days, months, or years?
- Place: Did the killings occur in a single location, or in a variety of places?
- Method: How were the victims killed?"
In the late decades of the 20th century and early years of the 2000s, the most popular classifications moved to include method, time and place. While such classifications may assist in gaining human meaning, as human-selected categories, they can also carry significant meaning and reflect a particular point of view of the commentator who assigned the descriptor.
- Crimes against humanity
- List of rampage killers
- Mass grave
- School shooting
- Suicide attack
- War crime
- Aggrawal A. (2005) Mass Murder. In: Payne-James JJ, Byard RW, Corey TS, Henderson C (Eds.) Encyclopedia of Forensic and Legal Medicine, Vol. 3, Pp. 216-223. Elsevier Academic Press, London
- "Serial Murder - Federal Bureau of Investigation". Fbi.gov. Retrieved 2012-03-07.
- Clues to Mass Rampage Killers: Deep Backstage, Hidden Arsenal, Clandestine Excitement, Randall Collins, The Sociological Eye, September 1, 2012
- Best, Joel (2013-06-16). "How Should We Classify the Sandy Hook Killings? : The social construction of a mass shooting epidemic". Reason. Retrieved 2013-06-18.
it is possible to characterize Newtown as an instance of a lot of different social problems: as a mass shooting; as a school shooting; as mass murder; as workplace violence (remember the staff members who were killed were at work); as a crime involving an assault rifle; as a case of a mentally ill person committing acts of violence; and so on. We expect journalists to have a sort of sociological imagination, to help us understand incidents as instances. And we can understand why advocates for gun control, mental health, or other causes might favor particular labels but we need to appreciate there is no One True Classification, that the categories we use are merely tools that may help us better understand what [is] happening in our society.
- R. J. Rummel, Irving Louis Horowitz, Death by Government, Page 35, ISBN 1-56000-927-6
- R.J. Rummel. Chapter 1: 61,911,000 Victims: Utopianism Empowered
- Akbar, Arifa (17 September 2010). "Mao's Great Leap Forward 'killed 45 million in four years'". The Independent (London). Retrieved 20 September 2010.
- Kluger, Jeffrey (April 19, 2007). "Inside a Mass Murderer's Mind". Time. Retrieved May 12, 2010.
- "ABC News: What Pushes Shooters to Mass Murder?". Abcnews.go.com. 2008-02-09. Retrieved 2012-03-07.
- "Notoriety Drives Mass Shooters". Newser. Retrieved 2012-03-07.
- "ABC News: Psychiatrist: Showing Video Is 'Social Catastrophe'". Abcnews.go.com. 2007-04-19. Retrieved 2012-03-07.
- "Nepal royal family massacred". BBC News. June 2, 2001
- Farhi, Paul (December 20, 2012). "Adam Lanza, and others who committed mass shootings, were white males". The Washington Post.
- 2014 Isla Vista killings
- Sebag Montefiore, Simon (2004). Stalin: The Court of the Red Tsar. Knopf. p. 334. ISBN 1-4000-4230-5.
- Erica Goode (April 6, 2013). "In Shift, Police Advise Taking an Active Role to Counter Mass Attacks". The New York Times. Retrieved April 7, 2013.
- What makes a Mass Killer?
- Mass Murder: A Small Person's Way to Immortality[dead link]
- Mass shootings interactive map
- Online Encyclopedia of Mass Violence
- Timeline: Deadliest U.S. mass shootings
- Public Mass Shootings in the United States: Selected Policy Implications Congressional Research Service
- Algoworld: Scientific Ways To Predict Mass Shootings