Mass shootings in the United States
Mass shootings are incidents involving multiple victims of firearm-related violence. The precise inclusion criteria are disputed, and there is no broadly accepted definition. One definition is an act of public firearm violence—excluding gang killings, domestic violence, or terrorist acts sponsored by an organization—in which a shooter kills at least four victims. Using this definition, one study found that nearly one-third of the world's public mass shootings between 1966 and 2012 (90 of 292 incidents) occurred in the United States. Using a similar definition, The Washington Post records 163 mass shootings in the United States between 1967 and June 2019.
Gun Violence Archive, frequently cited by the press, defines a mass shooting as firearm violence resulting in at least four people being shot at roughly the same time and location, excluding the perpetrator. Using this definition, there have been 2,128 mass shootings since 2013, roughly one per day.
According to some studies, the United States has had more mass shootings than any other country, however they accounted for less than 0.2% of homicides between 2000 and 2016. Shooters generally either die by suicide afterwards or are restrained or killed by law enforcement officers or civilians.
There is no fixed definition of a mass shooting in the United States. The Investigative Assistance for Violent Crimes Act of 2012, signed into law in January 2013, defines a mass killing as one resulting in at least three victims, excluding the perpetrator. In 2015, the Congressional Research Service (CRS), while not defining a mass shooting, does define a public mass shooting—for the purposes of its report entitled "Mass Murder with Firearms"—as "a multiple homicide incident in which four or more victims are murdered with firearms, within one event, and in one or more locations in close proximity". The CRS further states that its report "attempts to refine the relatively broad concept of mass shooting... into a narrower formulation: public mass shootings." A broader definition, as used by the Gun Violence Archive, is that of "four or more shot or killed, not including the shooter". The latter definition is often used by the media, press, and non-profit organizations.
Some studies indicate that the rate at which public mass shootings occur has tripled since 2011. Between 1982 and 2011, a mass shooting occurred roughly once every 200 days. However, between 2011 and 2014, that rate has accelerated greatly with at least one mass shooting occurring every 64 days in the United States.
In recent years, the number of public mass shootings has increased substantially, although there has been an approximately 50% decrease in firearm homicides in the nation overall since 1993. The decrease in firearm homicides has been attributed to better policing, a better economy and environmental factors such as the removal of lead from gasoline.
A comprehensive report by USA Today tracked all mass killings from 2006 through 2017 in which the perpetrator willfully killed 4 or more people. For mass killings by firearm for instance, it found 271 incidents with a total of 1,358 victims. Mother Jones listed seven mass shootings, defined as indiscriminate rampages in public places resulting in four or more victims killed, in the U.S. for 2015. An analysis by Michael Bloomberg's gun violence prevention group, Everytown for Gun Safety, identified 110 mass shootings, defined as shootings in which at least four people were murdered with a firearm, between January 2009 and July 2014; at least 57% were related to domestic or family violence.
Other media outlets have reported that hundreds of mass shootings take place in the United States in a single calendar year, citing a crowd-funded website known as Shooting Tracker which defines a mass shooting as having four or more people injured or killed. In December 2015, The Washington Post reported that there had been 355 mass shootings in the United States so far that year. In August 2015, The Washington Post reported that the United States was averaging one mass shooting per day. An earlier report had indicated that in 2015 alone, there had been 294 mass shootings that killed or injured 1,464 people. Shooting Tracker and Mass Shooting Tracker, the two sites that the media have been citing, have been criticized for using a broader criteria—counting four victims injured as a mass shooting—thus producing much higher figures.
Mass shootings tend to occur in clusters. When one occurs another is likely to follow, according to research by the Violence Project.
According to The New York Times, the majority of perpetrators they have published stories about are white males who act alone. According to most analyses and studies, the proportion of mass shooters in the United States who are white is slightly less than the proportion of white people in the general population of the US, however, the proportion of male mass shooters is considerably greater than the proportion of males in the population. According to the Associated Press, white men comprise nearly 50 percent of all mass shooters in the US. According to the Center for Inquiry, mass shootings of family members (the most common) are usually carried out by White, middle-aged men. Felony mass shootings (connected with a previous crime) tend to be committed by young Black or Hispanic males with extensive criminal records, typically against persons of the same ethnic group. Public mass shootings of persons unrelated to the shooter, and for a reason not connected with a previous crime (the rarest but most publicized) are committed by men whose racial distribution closely matches that of the nation as a whole. Other than gender, the demographic profiles of public mass shooters are too varied to draw firm conclusions.
- Higher accessibility and ownership of guns. The US has the highest per-capita gun ownership in the world with 120.5 firearms per 100 people; the second highest is Yemen with 52.8 firearms per 100 people.
- Mental illness and its treatment (or the lack thereof) with psychiatric drugs. This is controversial. Many of the mass shooters in the U.S. suffered from mental illness, but the estimated number of mental illness cases has not increased as significantly as the number of mass shootings.
- The desire to seek revenge for a long history of being bullied at school and/or at the workplace. In recent years, citizens calling themselves "targeted individuals" have cited adult bullying campaigns as a reason for their deadly violence.
- The widespread chronic gap between people's expectations for themselves and their actual achievement, and individualistic culture. Some analysts and commentators place the blame on contemporary capitalism and neoliberalism.
- Desire for fame and notoriety. Also, mass shooters learn from one another through "media contagion," that is, "the mass media coverage of them and the proliferation of social media sites that tend to glorify the shooters and downplay the victims."
- The copycat phenomenon.
- Failure of government background checks due to incomplete databases and/or staff shortages.
A panel of mental health and law enforcement experts has estimated that roughly one-third of acts of mass violence—defined as crimes in which four or more people were killed—since the 1990s were committed by people with a serious mental illness. However, the study emphasized that people with serious mental illness are responsible for less than 4% of all the violent acts committed in the United States.
Additionally, in February 2021, Psychological Medicine published a survey reviewing 14,785 publicly reported murders in English language news worldwide between 1900 and 2019 compiled in a database by psychiatrists at the New York State Psychiatric Institute and the Columbia University Irving Medical Center that found that of the 1,315 personal-cause mass murders (i.e. driven by personal motivations and not occurring within the context of war, state-sponsored or group-sponsored terrorism, gang activity, or organized crime) only 11 percent of mass murderers and only 8 percent of mass shooters had a "serious mental illness" (e.g. schizophrenia, bipolar disorder, major depressive disorder), that mass shootings have become more common than other forms of mass murder since 1970 (with 73 percent occurring in the United States alone), and that mass shooters in the United States were more likely to have legal histories, to engage in recreational drug use or alcohol abuse, and to display non-psychotic psychiatric or neurologic symptoms.
Survey coauthor psychiatrist Paul S. Appelbaum argued that the data from the survey indicated that "difficulty coping with life events seem more useful foci for prevention [of mass shootings] and policy than an emphasis on serious mental illness", while psychiatrist Ronald W. Pies has suggested that psychopathology should be understood as a three-gradation continuum of mental, behavioral and emotional disturbance with most mass shooters falling into a middle category of "persistent emotional disturbance". In 2014, the Federal Bureau of Investigation conducted a survey of 160 active shooter cases in 40 states and the District of Columbia between 2000 and 2013 (averaging approximately 11 cases annually) that found that 112 incidents (70%) took place in a business, commercial, or educational environment, 96 incidents (60%) ended before police arrived, in 64 incidents (40%) the shooter committed suicide and 64 also qualified as mass murder, while in only 6 incidents (4%) was the perpetrator female and in only 2 incidents (1%) was there more than one perpetrator.
In 2015, psychiatrists James L. Knoll and George D. Annas noted that the tendency of most media attention following mass shootings on mental health leads to sociocultural factors being comparatively overlooked. Instead, Knoll and Annas cite research by social psychologists Jean Twenge and W. Keith Campbell on narcissism and social rejection in the personal histories of mass shooters, as well as cognitive scientist Steven Pinker's suggestion in The Better Angels of Our Nature (2011) that further reductions in human violence may be dependent upon reducing human narcissism. In The Upswing (2020), political scientist Robert D. Putnam and Shaylyn Romney Garrett used the Google Ngram Viewer to plot usage of the words "we" and "I" in any books published in any year in the United States and found that the ratio of usage of "we" to "I" has declined since the mid-1960s.
In July 2018, a meta-analysis published in Psychology of Popular Media found that grandiose narcissism positively correlated with time spent on social media, frequency of status updates, number of friends or followers, and frequency of posting self-portrait digital photographs, while a meta-analysis published in the Journal of Personality in April 2018 found that the positive correlation between grandiose narcissism and social networking service usage was replicated across platforms (including Facebook and Twitter). In March 2020, the Journal of Adult Development published a regression discontinuity analysis of 254 Millennial Facebook users investigating differences in narcissism and Facebook usage between the age cohorts born from 1977 to 1990 and from 1991 to 2000 and found that the later born Millennials scored significantly higher on both. In June 2020, Addictive Behaviors published a systematic review finding a consistent, positive, and significant correlation between grandiose narcissism and problematic social media use. Also in 2018, social psychologist Jonathan Haidt and FIRE President Greg Lukianoff noted in The Coddling of the American Mind that former Facebook president Sean Parker stated in a 2017 interview that the Facebook like button was consciously designed to prime users receiving likes to feel a dopamine rush as part of a "social-validation feedback loop".
Several types of guns have been used in mass shootings in the United States. A 2014 study conducted by Dr. James Fox of 142 shootings found that 88 (62%) were committed with handguns of all types; 68 (48%) with semi-automatic handguns, 20 (14%) with revolvers, 35 (25%) with semi-automatic rifles, and 19 (13%) with shotguns. The study was conducted using the Mother Jones database of mass shootings from 1982 to 2018. High capacity magazines were used in approximately half of mass shootings. Semi-automatic rifles have been used in six of the ten deadliest mass shooting events.
Deadliest mass shootings since 1949Edit
The following mass shootings are the deadliest to have occurred in modern U.S. history. Only incidents with ten or more civilian fatalities are included. This list starts in 1949, the year in which Howard Unruh committed his shooting, the first to incur ten or more fatalities.
- Was previously the deadliest mass shooting
|Incident||Year||Location||Deaths||Injuries||Type of firearm(s) used||Ref(s)|
|1||Las Vegas shooting||2017||Paradise, Nevada||60 (plus 1 perp.)[fn 1]||867 (411 from gunfire)||Semi-automatic rifles (some outfitted with bump stocks), bolt-action rifle, and revolver|||
|2||Orlando nightclub shooting||2016||Orlando, Florida||49 (plus 1 perp.)||58 (53 from gunfire)||Semi-automatic rifle and pistol|||
|3||Virginia Tech shooting||2007||Blacksburg, Virginia||32 (plus 1 perp.)||23 (17 from gunfire)||Semi-automatic pistols|||
|4||Sandy Hook Elementary School shooting||2012||Newtown, Connecticut||27 (plus 1 perp.)||2||Semi-automatic rifle, bolt-action rifle, and pistol|||
|5||Sutherland Springs church shooting||2017||Sutherland Springs, Texas||26 (plus 1 perp.)[fn 2]||22||Semi-automatic rifle|||
|6||Luby's shooting||1991||Killeen, Texas||23 (plus 1 perp.)||27||Semi-automatic pistols|||
|El Paso Walmart shooting||2019||El Paso, Texas||23[fn 3]||23||Semi-automatic rifle|||
|8||San Ysidro McDonald's massacre||1984||San Diego, California||21 (plus 1 perp.)||19||Semi-automatic carbine, pistols, and shotgun|||
|9||University of Texas tower shooting||1966||Austin, Texas||17 (plus 1 perp.)[fn 2][fn 4]||31||Bolt-action rifle, semi-automatic carbine, revolver, semi-automatic pistols, and pump-action shotgun|||
|Stoneman Douglas High School shooting||2018||Parkland, Florida||17||17||Semi-automatic rifle|||
|11||Edmond post office shooting||1986||Edmond, Oklahoma||14 (plus 1 perp.)||6||Semi-automatic pistols|||
|Fort Hood shooting||2009||Killeen, Texas||14[fn 2]||32 (plus 1 perp.)||Semi-automatic pistol and revolver|||
|San Bernardino attack||2015||San Bernardino, California||14 (plus 2 perps.)||24||Semi-automatic rifles|||
|14||Camden shootings||1949||Camden, New Jersey||13||3||Semi-automatic pistol|||
|Wilkes-Barre shootings||1982||Wilkes-Barre, Pennsylvania||13||1||Semi-automatic rifle|||
|Wah Mee massacre||1983||Seattle, Washington||13||1||Semi-automatic pistol(s) and/or revolver(s)[fn 5]|||
|Columbine High School massacre||1999||Columbine, Colorado||13 (plus 2 perps.)||24 (21 from gunfire)||Semi-automatic carbine, semi-automatic pistol, and shotguns|||
|Binghamton shooting||2009||Binghamton, New York||13 (plus 1 perp.)||4||Semi-automatic pistols|||
|19||Aurora theater shooting||2012||Aurora, Colorado||12||70 (58 from gunfire)||Semi-automatic rifle, pistol, and shotgun|||
|Washington Navy Yard shooting||2013||Washington, D.C.||12 (plus 1 perp.)||8 (3 from gunfire)||Semi-automatic pistol and shotgun|||
|Thousand Oaks shooting||2018||Thousand Oaks, California||12 (plus 1 perp.)[fn 6]||16 (1 from gunfire)||Semi-automatic pistol|||
|Virginia Beach shooting||2019||Virginia Beach, Virginia||12 (plus 1 perp.)||4||Semi-automatic pistols|||
|23||Easter Sunday massacre||1975||Hamilton, Ohio||11||0||Semi-automatic pistols and revolver|||
|Pittsburgh synagogue shooting||2018||Pittsburgh, Pennsylvania||11||6 (plus 1 susp.)||Semi-automatic rifle and pistols|||
|25||Palm Sunday massacre||1984||Brooklyn, New York||10||0||Semi-automatic pistols|||
|Geneva County shootings||2009||Geneva County, Alabama||10 (plus 1 perp.)||6||Semi-automatic rifles, revolver, and shotgun|||
|Santa Fe High School shooting||2018||Santa Fe, Texas||10||13 (plus 1 susp.)||Shotgun and revolver|||
|Boulder shooting||2021||Boulder, Colorado||10||1 (plus 1 susp.)[fn 7]||Semi-automatic pistols|||
- including 2 victims who died due to complications in 2019 and 2020
- The fatality total includes an unborn child.
- including 1 victim who died due to complications in 2020
- including 1 victim who died due to complications in 2001
- During the massacre, the perpetrators used three .22 caliber handguns of an unknown type that were never recovered by the authorities.
- One of the victims was killed by stray police gunfire
- The civilian injury was indirect
- Follman, Mark; Aronsen, Gavin; Pan, Deanna (August 4, 2019). "US Mass Shootings, 1982–2019: Data from Mother Jones' investigation". Mother Jones. Retrieved August 10, 2019.
- Borchers, Callum (October 4, 2017). "The squishy definition of 'mass shooting' complicates media coverage". Washington Post. Retrieved August 26, 2018.
...'mass shooting' is a term without a universally-accepted definition.
- Bjelopera, Jerome (March 18, 2013). "Public Mass Shootings in the United States" (PDF). Congressional Research Service. Archived from the original (PDF) on September 9, 2013. Retrieved August 26, 2018.
There is no broadly agreed-to, specific conceptualization of this issue, so this report uses its own definition for public mass shootings.
- Greenberg, Jon; Jacobson, Louis; Valverde, Miriam (February 14, 2018). "What we know about mass shootings". PolitiFact. Tampa Bay Times. Retrieved February 20, 2018.
As noted above, there is no widely accepted definition of mass shootings. People use either broad or restrictive definitions of mass shootings to reinforce their stance on gun control. After the 2012 Sandy Hook school shooting, Congress defined "mass killings" as three or more homicides in a single incident. The definition was intended to clarify when the U.S. Attorney General could assist state and local authorities in investigations of violent acts and shootings in places of public use.
- Christensen, Jen (October 5, 2017). "Why the US has the most mass shootings". CNN. Retrieved November 6, 2017.
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- Berkowitz, Bonnie; Gamio, Lazaro; Lu, Denise; Uhrmacher, Kevin; Lindeman, Todd. "The terrible numbers that grow with each mass shooting". Washington Post. Retrieved November 5, 2017.
- "Report: U.S. averages nearly one mass shooting per day so far in 2017". CBS News.
- "General Methodology". Gun Violence Archive.
- Morris, Sam; Team, Guardian US Interactive; Morris, Sam; Team, Guardian US Interactive. "Mass shootings in the US: there have been 1,624 in 1,870 days". The Guardian.
- "One-Third of Mass Shootings Committed by People with Mental Illness, Study Says".
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- Michaels, Samantha (August 23, 2015). "The United States Has Had More Mass Shootings Than Any Other Country". Mother Jones. Retrieved October 2, 2017.
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- Blair, John Pete; Schweit, Katherine W. (2014), A Study of Active Shooter Incidents, 2000–2013 (PDF), Washington, DC: Texas State University and Federal Bureau of Investigation
- Cherney, Elyssa (August 5, 2019). "The Same Weekend as Massacres in El Paso and Dayton, 15 People Were Shot in 2 Chicago Incidents. Why Aren't Those Called Mass Shootings Too?". Chicago Tribune. Retrieved August 7, 2019.
Different organizations use a variety of measures to determine whether an act of gun violence meets the criteria of a mass shooting.... How you define the term results in vastly different counts: The Gun Violence Archive has tallied 255 mass shootings in 2019 so far, while Mother Jones lists the number at seven. Some databases also exclude gang-related or domestic shootings.... Researchers on both sides of the spectrum say that data about mass shootings can be misleading if not presented with a clear methodology.
- "H.R. 2076 (112th): Investigative Assistance for Violent Crimes Act of 2012". govtrack.us. United States Congress. Retrieved February 20, 2018.
(I)the term mass killings means 3 or more killings in a single incident;
- Ingraham, Christopher (December 3, 2015). "What makes a 'mass shooting' in America". Washington Post. Retrieved November 5, 2017.
But starting in 2013, federal statutes defined "mass killing" as three or more people killed, regardless of weapons.
- Follman, Mark. "What Exactly Is A Mass Shooting". Mother Jones. Retrieved August 9, 2015.
In January 2013, a mandate for federal investigation of mass shootings authorized by President Barack Obama lowered that baseline to three or more victims killed.
- Krouse, William J.; Richardson, Daniel J. (July 30, 2015). "Mass Murder with Firearms: Incidents and Victims, 1999–2013" (PDF). FAS.org. Congressional Research Service. Retrieved October 28, 2019.
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- "Orlando club shootings: Full fury of gun battle emerges". BBC News. June 13, 2016. Retrieved June 13, 2016. Cites Mass Shooting Tracker
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- Housley, Adam; La Jeunesse, William; Gibson, Jake; Herridge, Catherine; Arroyo, Mike; Singman, Brooke; Fedschun, Travis (October 2, 2017). "Las Vegas shooting: At least 58 dead in massacre Trump calls 'act of pure evil'". Fox News. Associated Press. Retrieved October 2, 2017.
- Lacanlale, Rio (August 24, 2020). "California woman declared 59th victim of 2017 massacre in Las Vegas". The Las Vegas Review-Journal. Retrieved August 27, 2020.
- Lacanlale, Rio (September 17, 2020). "Las Vegas woman becomes 60th victim of October 2017 mass shooting". The Las Vegas Review-Journal. Retrieved September 17, 2020.
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- Ehrenfreund, Max (December 3, 2015). "We've had a massive decline in gun violence in the United States. Here's why". Washington Post. ISSN 0190-8286. Retrieved December 13, 2017.
- "Behind the Bloodshed". USA Today. Retrieved December 3, 2015.
- Follman, Mark; Aronsen, Gavin; Pan, Deanna (June 12, 2016). "A Guide to Mass Shootings in America". Mother Jones. Retrieved June 13, 2016.
- Follman, Mark; Aronsen, Gavin; Pan, Deanna. "US Mass Shootings, 1982–2016: Data From Mother Jones' Investigation". Mother Jones. Retrieved June 13, 2016. Original date December 28, 2012; list updated every 5 minutes. Figures for years 2011–2015: 3, 7, 5, 4, 7.
- Jeltsen, Melissa (July 18, 2014). "Mass Shooting Analysis Finds Strong Domestic Violence Connection". The Huffington Post. Retrieved June 13, 2016.
- "Analysis of Mass Shootings". Everytown for Gun Safety. August 20, 2015. Retrieved June 13, 2016. This analysis has later figures than reported in the article
- "The San Bernardino shooting is the second mass shooting today and the 355th this year". The Washington Post. December 2, 2015. Retrieved December 16, 2015.
- Ingraham, Christopher (August 26, 2015). "We're now averaging more than one mass shooting per day in 2015". The Washington Post. Retrieved September 6, 2015.
- "More than one mass shooting happens per day in the U.S., data shows". PBS NewsHour. October 2, 2015.
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- Derosa, Anthony (April 17, 2021). "Indianapolis FedEx Shooting: Brandon Hole, the Victims, What We Know". Wall Street Journal.
- Victor, Daniel (February 17, 2018). "Mass Shooters Are All Different. Except for One Thing: Most Are Men". The New York Times. Retrieved April 10, 2018.
About the only thing almost all of them have in common is that they are men. [...] Examining past New York Times coverage of mass shootings reveals some shared tendencies of the gunmen, including the fact that they are most commonly white
- Engber, Daniel (October 6, 2017). "What the White Mass-Shooter Myth Gets Right and Wrong About Killers' Demographics". Slate Magazine. Retrieved August 4, 2019.
roughly 70 percent of the shooters in mass killings were white—certainly a majority. But according to Census Bureau estimates for 2012, whites accounted for 73.9 percent of all Americans" "men are even more overrepresented among mass shooters and mass killers than they are among “normal” killers
- "Mass shootings so far this year almost reach 2018 levels". AP NEWS. August 8, 2019. Retrieved March 26, 2021.
The AP/USA Today/Northeastern database shows that many mass shootings are committed by a certain demographic: young, white men. Most mass shootings in the U.S. are carried out by men, with white men making up nearly 50 percent of the shooters, the database shows.
- Radford, Benjamin (May 31, 2019). "Who Are Mass Shooters? Mass Shooter Demographics". Center for Inquiry. Retrieved March 30, 2021.
The topic of mass shootings is fraught not only with political agendas but also with rampant misinformation. Facile comparisons and snarky memes dominate social media, crowding out objective, evidence-based evidence and analysis. This is effective for scoring political points but wholly counterproductive for understanding the nature of the problem and its broader issues.
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...high-capacity magazines have been used in more than half of mass shootings over four decades, according to several studies.
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