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. Shooters generally either die by suicide afterwards or are restrained or killed by law enforcement officers or civilians. However, mass shootings accounted for less than 0.2% of all homicides in the United States between 2000 and 2016.
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 3 victims, excluding the perpetrator. In 2015, the Congressional Research Service does not define a mass shooting but 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 "4 or more shot or killed, not including the shooter". This definition, of four people shot regardless of whether or not that results in injury or death, 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.
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 U.S., however the proportion of male mass shooters is considerably greater than the proportion of males.
- 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 individual" 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.
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 1949
The following mass shootings are the deadliest to have occurred in modern U.S. history (1949 to present). Only incidents with ten or more victim fatalities are included. The death tolls reflect the numbers given by police in the days after the shootings.
- 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||58 (plus 1 perp.)[fn 1]||869 (413 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 and pistol|||
|5||Sutherland Springs church shooting||2017||Sutherland Springs, Texas||26 (plus 1 perp.)[fn 2]||20||Semi-automatic rifle|||
|6||Luby's shooting||1991||Killeen, Texas||23 (plus 1 perp.)||27||Semi-automatic pistols|||
|7||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||Stoneman Douglas High School shooting||2018||Parkland, Florida||17||17||Semi-automatic rifle|||
|10||University of Texas tower shooting||1966||Austin, Texas||16 (plus 1 perp.)[fn 2][fn 4]||32||Bolt-action rifle, semi-automatic carbine, revolver, semi-automatic pistols, and pump-action shotgun|||
|11||Edmond post office shooting||1986||Edmond, Oklahoma||14 (plus 1 perp.)||6||Semi-automatic pistols|||
|San Bernardino attack||2015||San Bernardino, California||14 (plus 2 perps.)||24||Semi-automatic rifles|||
|Fort Hood shooting||2009||Killeen, Texas||14[fn 2]||32 (plus 1 perp.)||Semi-automatic pistol and revolver|||
|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, shotguns|||
|Binghamton shootings||2009||Binghamton, New York||13 (plus 1 perp.)||4||Semi-automatic pistols|||
|19||Atlanta shootings||1999||Stockbridge and Atlanta, Georgia||12 (plus 1 perp.)||13||Pistol|
|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.)||16 (1 from gunfire)||Semi-automatic pistol|||
|Virginia Beach shooting||2019||Virginia Beach, Virginia||12 (plus 1 perp.)||4||Semi-automatic pistols|||
|24||Easter Sunday massacre||1975||Hamilton, Ohio||11||0||Semi-automatic pistols and revolver|||
|Pittsburgh synagogue shooting||2018||Pittsburgh, Pennsylvania||11||6 (plus 1 perp.)||Semi-automatic rifle, semi-automatic pistols|||
|26||Palm Sunday massacre||1984||Brooklyn, New York||10||0||Semi-automatic pistols|||
|Geneva County massacre||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||14 (plus 1 perp.)||Shotgun and revolver|||
- plus 2 victims who died due to complications in 2019 and 2020
- The fatality total includes an unborn child.
- 1 victim died due to complications in 2020
- plus 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.
- 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.
- Lankford, Adam (2016). "Public Mass Shooters and Firearms: A Cross-National Study of 171 Countries". Violence and Victims. 31 (2): 187–99. doi:10.1891/0886-6708.VV-D-15-00093. PMID 26822013. S2CID 207266615.
- 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.
- Palazzolo, Joe; Flynn, Alexis (October 3, 2015). "U.S. Leads World in Mass Shootings". The Wall Street Journal. Retrieved October 2, 2017.
- Healy, Melissa (August 24, 2015). "Why the U.S. is No. 1 – in mass shootings". Los Angeles Times. Retrieved October 2, 2017.
- Michaels, Samantha (August 23, 2015). "The United States Has Had More Mass Shootings Than Any Other Country". Mother Jones. Retrieved October 2, 2017.
- Fox, Kara (March 9, 2018). "How US gun culture compares with the world in five charts". CNN.
- 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
- One-Third of Mass Shootings Committed by People With Mental Illness, Study Says | The Pew Charitable Trusts
- 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.
- "General Methodology". Gun Violence Archive. Retrieved February 21, 2018.
- Nichols, Chris (October 4, 2017). "How is a 'mass shooting' defined?". PolitiFact California. Retrieved February 21, 2018.
- Christensen, Jen (August 28, 2015). "Why the U.S. has the most mass shootings". CNN.
- "About the Mass Shooting Tracker". Mass Shooting Tracker. Archived from the original on January 4, 2018. Retrieved June 13, 2016.
- "Orlando club shootings: Full fury of gun battle emerges". BBC News. June 13, 2016. Retrieved June 13, 2016. Cites Mass Shooting Tracker
- Axelrod, Jim (November 6, 2017). "Are Americans becoming 'numb' to mass shootings?". CBS News. Retrieved February 21, 2018.
- Cohen, Amy P.; Azrael, Deborah; Miller, Matthew (October 15, 2014). "Rate of mass shootings has tripled since 2011, new research from Harvard shows". Mother Jones. Retrieved December 13, 2017.
- 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.
- Follman, Mark (December 3, 2015). "How Many Mass Shootings Are There, Really?". The New York Times. Retrieved December 6, 2015.
- Stuart, Elizabeth (December 7, 2015). "Number of U.S. Mass Shootings Greatly Exaggerated in Media, Acclaimed Researcher States". Phoenix New Times. Retrieved December 10, 2015.
- 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
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- Fisher, Marc (February 15, 2018). "The AR-15: 'America's rifle' or illegitimate killing machine?". The Washington Post. Retrieved May 11, 2018.
...high-capacity magazines have been used in more than half of mass shootings over four decades, according to several studies.
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