Mass shootings in the United States

Incidents involving multiple victims of firearm violence

For a more comprehensive list, see List of mass shootings in the United States.

Memorials for some of the deadliest mass shootings that occurred in the United States. Clockwise from top left: The 2017 Las Vegas shooting, the Orlando nightclub shooting, the Virginia Tech shooting, the Sandy Hook Elementary School shooting, and the 2019 El Paso shooting.

Mass shootings are incidents involving multiple victims of firearm related violence. Definitions vary, with no single, broadly accepted definition.[1][2][3] 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, a 2016 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.[4][5] In 2017, The New York Times recorded the same total of mass shootings for that span of years.[6] Perpetrator demographics vary by type of mass shooting, though in almost all cases they are male. Contributing factors may include easy access to guns, perpetrator suicidality and life history factors, and sociocultural factors including online media reporting of mass shootings and declining social capital. However, reliable statistical generalizations about mass shootings are difficult to establish due to the absence of a universal definition for mass shootings, sources for data on mass shootings being incomplete and likely including biased samples of incidents, and mass shootings having low base rates.[7]

The Federal Bureau of Investigation designated 61 of all events in 2021 as active shooter incidents.[8] The United States has had more mass shootings than any other country.[4][9][10][11][12] After a shooting, perpetrators generally either commit suicide or are restrained or killed by law enforcement officers. Mass shootings accounted for under 0.2% of gun deaths in the United States between 2000 and 2016,[13] and less than 0.5% of all homicides in the United States from 1976 to 2018.[7]

## Definitions

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There is no fixed definition of a mass shooting in the United States,[3][14] and different researchers define "mass shootings" in different ways.[15] Of the 7 following definitions, most use a minimum of 4 victims as a threshold. Among the various definitions are those that are:

* Based on injuries:

* Gun Violence Archive: More broadly defines "mass shooting" to mean four or more (excluding the perpetrator) shot at roughly the same time and location, regardless of number of fatalities or the motive.[16][17][18] Brady: United Against Gun Violence uses a similar definition.[19]

* Mass Shooting Tracker: Defines "mass shooting" as "an incident where four or more people are shot in a single shooting spree," including the perpetrator or police shootings of civilians around the perpetrator, and irrespective of the motive of the perpetrator or the location of the murders.[20][21]

* Based on number of deaths:

* Investigative Assistance for Violent Crimes Act of 2012, signed into law in January 2013: Defines a "mass killing" as the killing of at least three victims, excluding the perpetrator, and regardless of the weapon used.[3][22][23][24]

* Everytown for Gun Safety, which tracks mass shootings based on press accounts, police records, and court papers, defines mass shooting as "any incident in which four or more people are shot and killed, excluding the shooter."[25]

* Based on number of deaths and nature of attack:

* Congressional Research Service (CRS) 2015 report titled Mass Murder with Firearms: Did not define "mass shooting" but defined "public mass shooting" for the purposes of its report 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."[26]

* Mother Jones's open-source database of mass shootings: The magazine's database, established after the 2012 Aurora movie theater massacre and updated continuously since that time, defines "mass shootings" as "indiscriminate rampages in public places resulting in four or more victims killed by the attacker," excluding "shootings stemming from more conventionally motivated crimes such as armed robbery or gang violence" and shootings in which the perpetrator has not been identified.[27][28] This definition generally is consistent with the FBI's figures and the data used by criminologists.[27]

* 2022 National Institute of Justice/The Violence Project dataset: Defines "mass public shooting" as an incident in which at least four victims were killed with firearms in a single event "and the murders are not attributable to any other underlying criminal activity or commonplace circumstance (armed robbery, criminal competition, insurance fraud, argument, or romantic triangle)."[29]

The FBI defines an "active shooter" incident as "one or more individuals actively engaged in killing or attempting to kill people in a populated area", excluding gun-related incidents that were the result of self-defense, gang or drug violence, residential or domestic disputes, crossfire as a byproduct of another ongoing criminal act, controlled barricade or hostage situations, or actions that appeared not to have put other people in peril.[8]

The appropriateness of a broad versus narrow definition of "mass shooting" has been the subject of debate. Some commentators argue in favor of a narrow definition of mass shootings that excludes the victims of street crime. Mark Follman of Mother Jones, which compiles an open-source database of mass shootings, contends that "While all the victims are important, conflating those many other crimes with indiscriminate slaughter in public venues obscures our understanding of this complicated and growing problem."[30] Northeastern University criminologist James Alan Fox argues against the use of the broad definition of "mass shooting" in the popular press, stating that it misleads readers.[31] Others, by contrast, argue that defining "mass shooting" solely as a shooting in a public place in which the perpetrator fires at random is too narrow.[21][32] For example, Mark Hay argues that although gang, party, and domestic violence "probably warrant different solutions" than random mass public shootings, a narrow definition fails "to capture and convey the full scope of large-scale gun violence in the United States" and its effect on marginalized communities.[32]

## Frequency

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The U.S. has substantially more mass shootings (in which four or more people are killed) than other developed countries.[33] A New York Times study reported how outcomes of active shooter attacks varied with actions of the attacker, the police (42% of total incidents), and bystanders (including a "good guy with a gun" outcome in 5.1% of total incidents).[34]

As of 2017, studies indicated 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.[35]

FBI data shows that active shooter incidents increased from 2000 to 2019.[13] Under the definition used by the Gun Violence Archive, by the end of 2019, there were 417 mass shootings; by the end of 2020, there had been 611; and by the end of 2021, 693.[36] By mid-May 2021, there were 10 mass shootings per week on average; by mid-May 2022, there was a total of 198 mass shootings in the first 19 weeks of the year, which represents 11 mass shootings a week.[37] The FBI designated 61 active shooter incidents.[38] There were ten mass shootings in 2019, two in 2020, and six in 2021.[39] Under the substantially narrower 2022 National Institute of Justice/The Violence Project dataset definition, there were 167 mass shootings (4 or more killed with firearms in public, not connected to "underlying criminal activity or commonplace circumstance") in the U.S. from 1966 to 2019, and 30.8% of the shootings occurred at the workplace.[29]

A comprehensive report by USA Today tracked all mass killings from 2006 through 2017 in which the perpetrator willfully killed four or more people. For mass killings by firearm for instance, it found 271 incidents with a total of 1,358 victims.[40]

In October 2018, PLOS One published a study analyzing 100 mass shootings from the Mother Jones database from January 1982 to May 2018 to evaluate whether mass shootings became more common in the United States over the preceding three decades. It found that mass shootings had steadily increased.[41] However, some researchers dispute whether the frequency of mass shootings is increasing due to differences in research methods and differences in the criteria used to define events as mass shootings.[13][42][7]

In 2018 The Washington Post recorded 163 mass shootings in the United States between 1967 and June 2019.[43] Mother Jones recorded 140 mass shootings between 1982 and February 2023.[44]

Under the Everytown for Gun Safety definition ("any incident in which four or more people are shot and killed, excluding the shooter") there were an average of 19 mass shootings in the U.S. each year from 2009 to 2020, with 947 wounded by gunfire and 1,363 fatally shot.[25] The report found that: "In nearly all mass shootings over this period, the shooter was an adult man who acted alone. Thirty-two percent of mass shooters, or 92 shooters, ended with the perpetrator committing suicide, and another 24 shooters were killed by responding law enforcement. The remaining 145 mass shooters were taken into custody by law enforcement, while the outcomes and identities of 23 remain unknown."[25] In 2022, the Violence Project of the National Institute of Justice recorded 185 mass shootings from 1966 to December 2022.[45] A 2023 report published in The Journal of the American Medical Association (JAMA) covering 2014 to 2022, found there had been 4,011 mass shootings in the US.[46]

## Perpetrator demographics

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See also: Lone wolf attack, Aggression § Gender, and Sex differences in crime

According to The New York Times, there is no common profile of people who carry out mass shootings in the United States, except that they are mostly men.[47] By race, according to a study, the proportion of mass shooters in the United States who are white is about equal to the overall proportion of white people in the general population of the US.[48][49] The proportion of male mass shooters is considerably larger than the proportion of males in the general population.[49] According to the Associated Press, white men comprise nearly 50% of all mass shooters in the US.[50] According to the National Institute of Justice/The Violence project study, the demographics of shooters were 97.7% male, with an average age of 34.1 years, 52.3% white, 20.9% black, 8.1% Latino, 6.4% Asian, 4.2% Middle Eastern, and 1.8% Native American.[29]

According to the Center for Inquiry, mass shootings of family members (the most common) are usually carried out by white, middle-aged males. Felony-related mass shootings (connected with a previous crime) tend to be committed by young Black or Hispanic males with extensive criminal records, typically against people 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.[51][52] Other than gender, the demographic profiles of public mass shooters are too varied to draw firm conclusions.[51] In a 2014 review of 160 active shooter incidents in the U.S. from 2000 to 2013 across 40 states and the District of Columbia, the FBI found that the perpetrator was female in only 6 of the 160 incidents (4%) and that in only 2 incidents (1%) was there more than one perpetrator.[53] Analogously, in December 2013, the Journal of Forensic Sciences published a sociodemographic network characteristics and antecedent behaviors survey of 119 lone-actor terrorists in the United States and Europe that found that 96.6% were male.[54]

## Contributing factors

[edit]

### High gun accessibility

[edit]

See also: Gun culture in the United States, Gun law in the United States, Gun laws in the United States by state, Gun politics in the United States, and Gun violence in the United States

Annual gun production in the U.S. has increased substantially in the 21st century, after having remained fairly level over preceding decades.[55] By 2023, a majority of U.S. states allowed adults to carry concealed guns in public.[55]

Multiple studies show that where people have easy access to firearms, gun-related deaths tend to be more frequent, including by suicide, homicide and unintentional injuries.[56]

Total deaths in U.S. mass shootings since 1982—defined as four or more people shot and killed in one incident, excluding the perpetrator, at a public place, excluding gang-related killings.[57][58]

After the 2004 expiration of the Federal Assault Weapons Ban, the firearms industry embraced the AR-15's political and cultural significance for marketing.[59] Almost every major gunmaker produces its own version, with ~16 million Americans owning at least one.[59]

Higher accessibility and ownership of guns has been cited as a reason for the U.S.'s high rate of mass shootings.[4][11][60] The U.S. 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.[60]

Researchers have found a reduction in the number of mass shooting related homicides while the Federal Assault Weapons Ban (FAWB) was in place from 1994 to 2004, which had banned certain types of semi-automatic rifles, including AR-15s.[61] However, researchers also acknowledged that it was difficult to prove that the ban was the cause of this.[62] Conversely, the RAND Corporation published a review in 2023 of five studies researching the effects of the FAWB and state assault weapons bans on the frequency and lethality of mass shootings and found the evidence to be inconclusive, and the review also evaluated two studies researching the effect of high-capacity magazine bans on reducing the frequency and lethality of mass shootings and found the evidence for an effect to be limited.[63][70]

Several types of guns have been used in mass shootings in the United States, including semi-automatic handguns, semi-automatic rifles, revolvers, and shotguns.[71] Of the 172 events from 1966 to 2019 classified as mass public shootings (four or more victims killed) in the U.S. by the dataset compiled by The Violence Project of the National Institute of Justice, perpetrators used handguns in 77.2% of cases and semi-automatic rifles in 25.1% of cases.[29] An earlier 2016 study by James Alan Fox and Emma E. Fridel similarly concluded that "rather than assault weapons, semiautomatic handguns are the weapons of choice for most mass shooters."[72] High-capacity magazines were used in more than half of mass shootings over the four decades up to 2018.[73] Although semi-automatic rifles are used in only 1% of overall shootings in the U.S., they are used in 25% of mass shootings,[74] and (as of 2018) in six of the ten deadliest mass shooting events.[75][76]

A study published in PLOS One in 2015 examined mass shootings in the U.S. from 2005 to 2013 (and school shootings in the U.S. from 1998 to 2013). The study authors found that the "state prevalence of firearm ownership is significantly associated with the state incidence of mass killings with firearms, school shootings, and mass shootings."[77] Conversely, the October 2018 PLOS One study assessed the impact of state-level gun ownership rates in predicting state-level mass shooting rates and found that state-level gun ownership rates were not statistically significantly associated with the number of mass shootings in each state. The researchers tested the possibility that the relationship between gun ownership and the mass shooting rate was being confounded by gun law permissiveness and found that gun law permissiveness was only nominally correlated with gun ownership and that gun ownership was not statistically associated with the mass shooting rate with or without gun law permissiveness being adjusted.[41]

A 2019 study published in The BMJ conducted a cross-sectional time series study of U.S. states from 1998 to 2015; the study found that "States with more permissive gun laws and greater gun ownership had higher rates of mass shootings, and a growing divide appears to be emerging between restrictive and permissive states."[78] The study specifically found that "A 10% increase in state gun ownership was associated with a significant 35.1% (12.7% to 62.7%, P=0.001) higher rate of mass shootings. Partially adjusted regression analyses produced similar results, as did analyses restricted to domestic and non-domestic mass shootings."[78] A 2020 study published in Law and Human Behavior examined the relationship of state guns laws and the incidence and lethality of mass shootings in the U.S. from 1976 to 2018. The study found that "laws requiring permits to purchase a gun are associated with a lower incidence of mass public shootings, and bans on large capacity magazines are associated with fewer fatalities and nonfatal injuries when such events do occur."[79] The study specifically found that large-capacity magazine bans were associated with approximately 38% fewer fatalities and 77% fewer nonfatal injuries when a mass shooting occurred.[79]

From 1966 to 2019, approximately 77% of mass shooters in the U.S. legally obtained the firearm used in the attacks.[29][74] The researchers that compiled The Violence Project dataset found that 80% of perpetrators in school shootings obtained the firearm from family members, workplace shooters tended to use legally owned handguns, and other public shooters were more likely to acquire firearms illegally.[80][81][82]

In a general research review on mass shootings released in 2021, RAND Corporation researchers noted that the relative rarity of mass shootings leads the statistical assumptions of the causal inference methods used in gun policy research to rarely hold and potentially result in exaggerated effect sizes and spurious effects, while high variability of characteristics of mass shootings make analysis of policies to address mass shootings subject to extremely low statistical power and unlikely to find statistically significant effects even where researchers use appropriate statistical models and where policies are effective at reducing mass shootings.[7]

### Perpetrator suicidality

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See also: Red flag law, Controversies about psychiatry § Nature of diagnosis, Classification of mental disorders § Criticism, and Gender differences in suicide

The body of the perpetrator of the 1989 Stockton schoolyard shooting is removed from the grounds of Cleveland Elementary School following his suicide.

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" (SMI). However, the study emphasized that people with an SMI are responsible for less than 4% of all the violent acts committed in the United States.[83] The American Psychiatric Association (APA) states that gun violence is a public health crisis and has repeatedly noted that the overwhelming majority of people with mental illness are not violent and "are far more likely to be victims of violent crime than perpetrators of violence."[84][85]

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 which 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) 11% of mass murderers and 8% of mass shooters had an SMI (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% occurring in the United States alone), and that mass shooters in the U.S. 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.[86][87]

Psychiatrist Paul S. Appelbaum argued that the data from the New York State Psychiatric Institute and Columbia University Irving Medical Center database of mass shootings show that "legal problems, substance and alcohol use, and difficulty coping with life events seem more useful foci for prevention [of mass shootings] and policy than an emphasis on serious mental illness."[88] In 2015, psychiatrists James L. Knoll and George D. Annas cited 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.[89][90] The Violence Project's comprehensive mass shooting database has shown that mass shooters share a sense of entitlement and seek scapegoats when they fail to achieve goals in life.[82] However, psychologist Peter F. Langman has argued that while mass shooters follow similar patterns, mass shooters do not fit a single psychological profile and the characterization of mass shooters as "friendless loners" is a stereotype.[91][82]

In 2018, the FBI Behavioral Analysis Unit released a survey of 63 active shooter cases between 2000 and 2013. It found that 62% of active shooters showed symptoms of mental health disorders, but those symptoms may have been "transient manifestations of behaviors and moods that would not be sufficient to warrant a formal diagnosis of mental illness" and that only one-fourth of active shooters surveyed had a formal diagnosis of any mental health disorder (and a psychotic disorder in only 3 cases). The survey concludes that given the high lifetime prevalence of the symptoms of mental illness among the U.S. population, "formally diagnosed mental illness is not a very specific predictor of violence of any type, let alone targeted violence."[92][82] 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."[93]

In 2022, Psychology, Public Policy, and Law published a study by Jillian Peterson, James Densley, and others, assessing the life history variables of 172 mass shooters from 1966 to 2019. The researchers found that symptoms of psychosis played no role in 69% of mass shootings.[94] In the October 2018 PLOS One study, the researchers studied whether state-level SMI rates predicted state-level mass shooting rates and found that state-level SMI rates did not predict state-level mass shooting rates.[41] In 2004, the U.S. Secret Service and the U.S. Department of Education issued a report analyzing 41 school shootings in the United States that found that 78% of the shooters surveyed had histories of suicidal ideation or attempted suicide.[95] In its 2014 active shooter incidents review, the FBI found that 96 of the 160 incidents (60%) ended before police arrived, and in 64 incidents (40%) the shooter committed suicide.[53]

In December 2021, the Journal of Threat Assessment and Management published a study comparing 171 public mass shooters and 63 active shooters in the United States from 1966 to 2019 (using cases compiled in The Violence Project's database) to the general population, homicide offenders, and people who die by suicide.[96] In comparison to the general population, mass shooters were more likely to have a history of mental health issues, to have lifetime thought disorders, and greater lifetime suicidal ideation, while in comparison to general homicide offenders, mass shooters four times more frequently premeditated their homicides, eight times more frequently killed strangers, and were more likely to experience suicidal ideation and commit suicide directly or by cop.[97] In comparison to people who committed suicide, mass shooters were actually more likely to have histories of suicidal ideation and were slightly more likely to premeditate the act.[98] However, like the APA, the researchers emphasized that having a formal mental health disorder diagnosis is more predictive of being a victim of violence rather than a perpetrator.[97]

In the 2021 RAND Corporation review, the researchers noted that while most research has concluded that persons with SMIs are statistically overrepresented among mass shooters, the research has not established that a causal relationship between SMIs and mass shootings exists, and that estimates of mental illness prevalence among mass shooters vary widely by the definition of mass shootings used and the methods for identifying mental illness among mass shooters.[7] In October 2022, the Journal of Forensic Sciences published a subsequent review of 82 mass murders in the Columbia University database that at least partially occurred in academic settings that found that 68% of the mass murder perpetrators and 81% of the mass shooters did not have an SMI and that 46% of the mass shootings surveyed ended with the perpetrator committing suicide, leading the researchers to conclude that their findings "strongly suggest that focusing on mental illness, particularly psychotic illness, when talking about mass school shooting risks is missing other factors that contribute to the vast majority of cases".[99][100]

In the December 2013 Journal of Forensic Sciences lone-actor terrorists survey, lone-actor attacks were rarely sudden or impulsive and the researchers have subsequently noted that a sizable subset of their subjects took preparations to maximize their chances of death by cop or suicide.[54][101][98] Based upon the similarities in premeditation and lifetime suicidal ideation, James Densley has argued, "Many of these mass shootings are angry suicides."[101] A 2021 cross-sectional study published in JAMA Network Open examining 170 perpetrators of mass public shootings from 1996 to 2019, found that 44% of mass shooters had leaked their plans prior to committing the act, and that "Leakage was associated with receiving counseling and suicidality, which suggests it may be best characterized as a cry for help from perpetrators prior to their act."[102] "These findings suggest that leakage is a critical moment for mental health intervention to prevent gun violence."[102]

### Perpetrator life histories

[edit]

See also: Person–situation debate, Fundamental attribution error, Base rate fallacy, and Law of large numbers

Psychologist Jillian Peterson and James Densley co-founded The Violence Project, a National Institute of Justice-funded project in which researchers studied every mass shooting since 1966, and approximately 150 mass shooters, and coded 50 life history variables for each.[80][81][82] Their data suggest that almost all mass shooting perpetrators had four life history variables in common: they had (1) commonly experienced early childhood trauma and exposure to violence; (2) "reached an identifiable crisis point in the weeks or months leading up to the shooting," often linked to a specific grievance; (3) researched previous mass shootings, with many being radicalized through the internet; and (4) obtained the means (firearms) to carry out the plan, with perpetrators obtaining weapons from family members in 80% of school shootings, workplace shooters tending to use legally owned handguns, and other public shooters being more likely to acquire firearms illegally.[80] A 2021 article in the journal Injury Epidemiology found that from 2014 to 2019, 59.1% of mass shootings in the United States were related to domestic violence, and the shooter either killed a family member or had a domestic violence history in 68.2% of mass shootings.[103]

In the December 2021 Journal of Threat Assessment and Management study, mass shooters were more likely to be unemployed and be unmarried in comparison to the general population, while in comparison to general homicide offenders, mass shooters were more likely to not be in an intimate relationship.[96][97] In the December 2013 Journal of Forensic Sciences lone-actor terrorists survey, a wide range of activities and experiences preceded lone actors attacks, many but not all lone-actors were socially isolated, lone-actors regularly engaged in a detectable and observable range of activities with a wider pressure group, social movement, or terrorist organization, and a subset of 106 subjects for whom relationship data was available found that 68.9% had never married or were divorced or separated from their spouse and only 27.7% were reported to have children.[54]

However, in the 2021 RAND Corporation review, the researchers noted that due to mass shootings having low base rates, "policies targeting individuals based on risk factors would result in an extremely high rate of false positives" and that the probability of individuals identified by even the most predictive risk factors to commit a mass shooting is "on the order of one in a million."[7]

In a Gallup survey conducted in September and October 2020 of 1,035 randomly selected U.S. adults in all 50 states and the District of Columbia, 30% reported personally owning a firearm and 44% reported living in a household that owned at least one firearm,[104] while the 2020 United States census enumerated the U.S. adult population to be approximately 258.3 million persons in 126.8 million households and the Gun Violence Archive recorded 610 mass shootings in the United States in the same year.[105][106][107] The 2021 National Survey on Drug Use and Health conducted by the Substance Abuse and Mental Health Services Administration estimated that 57.8 million U.S. adults had a mental illness and 14.1 million U.S. adults had an SMI,[108][109] while the Gun Violence Archive recorded 690 mass shootings in the United States in the same year.[107] In 2022, there were 49,449 suicides in the United States (a record high) and the suicide rate in 2022 reached its highest level since 1941 at 14.3 per 100,000 persons,[110][111] while the Gun Violence Archive recorded 646 mass shootings in the United States in the same year.[107][13]

From 1960 to 2011, the percentage of all U.S. adults who were married declined from 72 percent to a record low of 51 percent and from 1990 to 2015 the gap in the U.S. marriage rate by educational attainment widened,[112][113] while the percentage of U.S. adults over the age of 25 who had never married rose to a record high of one-fifth in 2014 (with the rate of growth in the category of never married U.S. adults over the age of 25 accelerating since 2000) and the percentage of U.S. adults living without spouses or partners rose to 42 percent by 2017.[114][115] The divorce rate in the United States more than doubled from 2.2 per 1,000 people in 1960 to 5.3 per 1,000 people by 1981 and then saw a long-term decline to 2.9 per 1,000 people by 2018.[116] The percentage of U.S. households with married couples and children declined from 40 percent in 1970 to 26 percent by 1997,[117] which fell further to 18 percent by 2021.[118] Also, the National Coalition Against Domestic Violence has estimated that more than 12 million Americans experience domestic violence in the U.S. each year.[119]

### Sociocultural factors

[edit]

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Mass shootings in the contiguous United States in 2025[120]

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Mass shootings in Hawaii in 2025

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Mass shootings in Puerto Rico in 2025

Psychiatrists James L. Knoll and George D. Annas also noted that considering that mass shootings committed by perpetrators with SMIs amount to less than 1% of all gun-related homicides (and that most gun deaths in the United States are suicides rather than homicides),[121] the tendency of most media attention following mass shootings on mental health leads to sociocultural factors being comparatively overlooked.[122] In the October 2022 Journal of Forensic Sciences review of the Columbia University database, the researchers also concluded that "To prevent future mass school shootings, we need to begin to focus on the cultural and social drivers of these types of events... rather than on individual predictors".[99][100]

British criminologist Peter Squires argued that mass shooters in Europe and the U.S. "tend to be loners with not much social support who strike out at their communities, schools and families", and noted that countries with high gun-ownership rates but greater social capital (such as Norway, Finland, Switzerland, and Israel) have fewer mass killings.[123] In its 2014 active shooter incidents review, the FBI found that 45.6% took place in a business or commercial setting, 16.9% occurred in schools, 7.5% in institutions of higher education, 9.4% in open spaces, 6.9% in (non-military) government properties, 3.1% in military sites, 4.4% in homes, 3.8% in places of worship, and 2.5% in healthcare settings.[53]

In 2019, the Journal of Crime & Justice published a study that found following the social disorganization theory in criminology and research on declining social capital in the United States by political scientist Robert D. Putnam that county-by-county residential instability associated with higher poverty rates and single-parent households and reduced civic engagement associated with younger populations and ethnic heterogeneity were both associated with greater mass shootings, and noted that the frequency of mass shootings in the United States had increased from 1970 to 2015 during a period Putnam identified with social capital decline in Bowling Alone (2000).[124] A subsequent study published by the Journal of Crime & Justice in 2022 that also referenced Putnam's research on social capital found that counties in the contiguous United States with a greater number of religious congregations per capita had lower probabilities and numbers of mass shootings.[125]

However, in the 2021 RAND Corporation review, the researchers noted that county-level characteristics that are associated with mass shootings are possibly confounded by most mass shootings occurring in urban areas.[7] The 2023 JAMA report showed mass shootings from 2014 to 2022 and related to crime, social violence, and domestic violence occurred most frequently in the Southeastern United States and Illinois. Mass shootings that did not fit any of these categories were geographically distributed more evenly across the country. The highest rate was found in the District of Columbia (10.4 shootings per one million people), followed by much lower rates in Louisiana (4.2 mass shootings per million) and Illinois (3.6 mass shootings per million).[46]

The 2019 Journal of Crime & Justice study found that a test of the Southern legacy of violence hypothesis found a robust negative association with mass shootings across two of four statistical models.[124] Similarly, while Putnam did not discuss mass shootings in Bowling Alone, after constructing a state-by-state social capital index, Putnam found that the higher statewide homicide rates in the Southern United States from 1980 to 1995 in comparison to the country as a whole was entirely explained by lower rates of social capital in the region rather than a Southern culture of honor, that differences in statewide homicides rates within the region and within the Northern United States were also entirely explained by differences in social capital, and that rural communities in the country had higher civic engagement and social capital than the cities and suburbs of major metropolitan areas.[126]

In the first edition of Bowling Alone, Putnam found that social capital in the United States sharply declined beginning in the 1960s, and that this was caused primarily by the expansion of television ownership by U.S. households (which grew from an ownership rate of 1 percent in 1948 to 75 percent by 1955), the gradual replacement of the Greatest Generation and Silent Generation birth year cohorts by the Baby boomer and Generation X birth year cohorts, and the effect of the television ownership expansion on Baby boomers and Generation X.[127][128][129] In the afterword to the second edition of Bowling Alone (2020), Putnam found that the expansion of internet access, social media, social networking services, online dating services, professional networking services, and e-commerce was probably accelerating the decline in social capital among the U.S. population, while mostly just reinforcing existing social connections rather than creating new ones (i.e. bonding social capital versus bridging social capital)—analogously to the effect that the expansion of telephone ownership by U.S. households had (which grew from an ownership rate of 1 percent in 1890 to a majority by 1946 and to 75 percent by 1957).[130][131][132]

Mass shooting contagion (the "copycat phenomenon") has been studied.[4] A study published in PLOS One in 2015 examined mass shootings in the U.S. from 2005 to 2013 (and school shootings in the U.S. from 1998 to 2013). The study authors found that "significant evidence that mass killings involving firearms are incentivized by similar events in the immediate past," concluding that: "On average, this temporary increase in probability lasts 13 days, and each incident incites at least 0.30 new incidents (p = 0.0015). We also find significant evidence of contagion in school shootings, for which an incident is contagious for an average of 13 days and incites an average of at least 0.22 new incidents (p = 0.0001)."[77]

The October 2018 PLOS One study found that state-level poverty rates and state-level population sizes did not predict state-level mass shooting rates, but did find that greater online media coverage and online search interest levels correlated with shorter intervals between any two consecutive incidents of mass shootings and the researchers concluded that their findings suggest that online media might correlate with an increasing incidence rate of mass shootings.[41] The Violence Project's comprehensive mass shooting database has shown that mass shootings tend to occur in clusters,[133] and that hate-motivated and fame-seeking mass shootings have increased since 2015.[134] Steven Pinker has also noted that much of the news media in the United States has an editorial policy of "if it bleeds, it leads".[135]

Other posited factors contributing to the prevalence of mass shootings include perpetrators' desire to seek revenge for perceived school or workplace bullying,[136] the widespread chronic gap between people's expectations for themselves and their actual achievement,[60] perpetrators' desire for fame and notoriety,[60][4] toxic masculinity (mass shootings are perpetrated almost exclusively by men and boys),[137] and a failure of government background checks due to incomplete databases and/or staff shortages.[138][139] Feminist activist and psychotherapist Harriet Fraad and Marxian economist Richard D. Wolff contend that "American hyper-capitalism" fosters loneliness and social alienation among American men who become mass shooters.[140] A 2019 analysis of mass shootings from 1990 to 2015 published in BMC Public Health found that communities with rising levels of income inequality are at an increased risk of mass shootings.[141]

## Effects

[edit]

### Political

[edit]

A British Journal of Political Science study first published in 2017 (and in print in 2019) found that increase in proximity to mass public shootings in the U.S. was associated with statistically significant and "substantively meaningful" increases in support for stricter gun control laws.[142] The study also found that repeated events, magnitude, and recency of mass shootings play a role with "proximity to repeated events, more horrific events and more recent events" increasing "the salience of gun violence, and thus ... support for gun control."[142] However, the study found that the "most powerful effects" in support or opposition to gun control "are driven by variables related to local culture, with pronounced but expected differences emerging between respondents in rural, conservative, and gun-heavy areas and those residing in urban, liberal areas with few firearm stores."[142] A separate 2019 replication study, extending the earlier panel analysis, found no evidence that mass shootings caused a "significant or substantively meaningful main effect" on attitudes toward gun control.[143] However, the study did find evidence that mass shootings "have polarizing effects conditional on partisanship": "That is, Democrats who live near a mass shooting even tend to become more supportive of gun control restrictions, while Republican attitudes shift in the opposite direction."[143] The study authors concluded, "To the extent that mass shootings may affect public opinion, the result is polarizing rather than consensus building."[143]

Research suggests that there are few, if any, effects on electoral outcomes. A 2020 study published in the American Political Science Review using data on school shootings from 2006 to 2018 concluded the incidents had "little to no effect on electoral outcomes in the United States."[144] Although a 2021 study in the same journal covering a broader time period (1980–2016) found that the vote share of the Democratic Party increased by an average of almost 5 percentage points in counties that had experienced a "rampage-style" school shooting,[145] these findings appear to be spurious and merely the result of the fact that shootings tend to happen in areas that were already trending Democratic rather than a response to gun violence.[146] Both studies found no increase in voter turnout.[144][145]

A 2021 study published in Proceedings of the National Academy of Sciences of the United States of America concluded that "mass shootings have a strong impact on the emotions of individuals, but the impact is politicized, limited to individuals living within the town or city where the incident occurs, and fades within a week of the incident."[147] The study authors suggested that this phenomenon could help explain why mass shootings in the U.S. have not led to meaningful policy reform efforts.[147]

### Public health

[edit]

The Welcome to Fabulous Las Vegas sign following the 2017 Las Vegas shootings[148][149][150]

A slightly wounded survivor of the San Ysidro McDonald's massacre, pictured shortly after the incident

A review article first published online in 2015 and then printed in January 2017 in the journal Trauma, Violence, & Abuse concluded that "mass shootings are associated with a variety of adverse psychological outcomes in survivors and members of affected communities". It says that, while "the psychological effects of mass shootings on indirectly exposed populations" is less well-understood, "there is evidence that such events lead to at least short-term increases in fears and declines in perceived safety."[151] Identified risk factors for adverse psychological outcomes have included, among others, demographics, greater proximity to the attack, acquaintance with victims, and less access to psychosocial resources.[151]

With the aftermath of the shooting being psychological, hospitals should acquire programs or help facilities for their patients. The most vulnerable patients are children and young adults due to the fact that their brains aren't fully developed. The likelihood of them developing PTSD, depression, anxiety, suicidal thoughts, and more, are extraordinarily high.[152] Studies show that 12.4% of mass shooting patients were diagnosed with some form of mental illness, most common being PTSD. Men show lower rates of developing PTSD unlike women who show higher rates. Men and women who fit the criteria for PTSD also showed that they gained depression.[152]

## Deadliest mass shootings since 1949

[edit]

class=notpageimage|

Deadliest mass shootings in the United States since 1949 (with 10 or more fatalities excluding perpetrators)

Main article: List of mass shootings in the United States

The following mass shootings are the deadliest to have occurred in modern U.S. history. Only incidents with ten or more fatalities by gunshots, excluding those of the perpetrators, are included. This list starts in 1949, the year in which Howard Unruh committed his shooting, which was the first in modern U.S. history to incur ten or more fatalities.[153]

† Was previously the deadliest mass shooting
Rank  | Incident | Year | Location | Deaths (excluding perp.) | Injuries | Type of firearm(s) used | Ref(s)

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1  | Las Vegas shooting | 2017 | Paradise, Nevada | 60 (plus the perp.)[fn 1] | 867 approx. (413+ from gunfire or shrapnel) | Semi-automatic rifles (some outfitted with bump stocks), bolt-action rifle, and revolver | [154][155][156]
2  | Pulse nightclub shooting † | 2016 | Orlando, Florida | 49 (plus the perp.) | 58 (53 from gunfire) | Semi-automatic rifle and pistol | [154][155]
3  | Virginia Tech shooting † | 2007 | Blacksburg, Virginia | 32 (plus the perp.) | 23 (17 from gunfire) | Semi-automatic pistols | [154]
4  | Sandy Hook Elementary School shooting | 2012 | Newtown, Connecticut | 27 (plus the perp.) | 2 | Semi-automatic rifle, bolt-action rifle, and pistol | [154]
5  | Sutherland Springs church shooting | 2017 | Sutherland Springs, Texas | 26 (plus the perp.)[fn 2] | 22 | Semi-automatic rifle | [155][157]
6  | Luby's shooting † | 1991 | Killeen, Texas | 23 (plus the perp.) | 27 | Semi-automatic pistols | [154]
El Paso Walmart shooting | 2019 | El Paso, Texas | 23[fn 3] | 23 | Semi-automatic rifle | [158][159][160][161]
8  | San Ysidro McDonald's massacre † | 1984 | San Diego, California | 22 (plus the perp.)[fn 2] | 19 | Semi-automatic carbine, pistol, and pump-action shotgun | [154]
9  | Uvalde school shooting | 2022 | Uvalde, Texas | 21 (plus the perp.) | 18 | Semi-automatic rifle | [162][163]
10  | Lewiston shootings | 2023 | Lewiston, Maine | 18 (plus the perp.) | 13 | Semi-automatic rifle | [164][165]
11  | Parkland high school shooting | 2018 | Parkland, Florida | 17 | 17 | Semi-automatic rifle | [166]
12  | University of Texas tower shooting † | 1966 | Austin, Texas | 15 (plus the perp.)[fn 2][fn 4][fn 5] | 31 | Bolt-action rifle, semi-automatic carbine, revolver, semi-automatic pistols, and semi-automatic shotgun | [154]
13  | Fort Hood shooting | 2009 | Fort Hood, Texas | 14[fn 2] | 32 (plus the perp.) | Semi-automatic pistol and revolver | [167][168]
San Bernardino attack | 2015 | San Bernardino, California | 14 (plus both perps.) | 24 | Semi-automatic rifles | [154][155]
Columbine High School massacre | 1999  | Columbine, Colorado | 14 (plus both perps.)[fn 6] | 23 (20 from gunfire) | Semi-automatic carbine, semi-automatic pistol, double-barreled shotgun and pump-action shotgun  | [169]
Edmond post office shooting | 1986 | Edmond, Oklahoma | 14 (plus the perp.) | 6 | Semi-automatic pistols | [154]
17  | Aurora theater shooting | 2012 | Aurora, Colorado | 13[fn 2] | 70 (58 from gunfire) | Semi-automatic rifle, pistol, and shotgun | [170][155][171][172]
Binghamton shooting | 2009 | Binghamton, New York | 13 (plus the perp.) | 4 | Semi-automatic pistols | [173]
Camden shootings † | 1949 | Camden, New Jersey | 13 | 3 (2 from gunfire) | Semi-automatic pistol | [174][175]
Wilkes-Barre shootings | 1982 | Wilkes-Barre, Pennsylvania | 13 | 1 | Semi-automatic rifle | [176][177][178]
Wah Mee massacre | 1983 | Seattle, Washington | 13 | 1 | Semi-automatic pistol(s) and/or revolver(s)[fn 7] | [179]
22  | Thousand Oaks shooting | 2018 | Thousand Oaks, California | 12 (plus the perp.)[fn 8] | 16 (1 from gunfire) | Semi-automatic pistol | [180][181]
Washington Navy Yard shooting | 2013 | Washington, D.C. | 12 (plus the perp.) | 8 (3 from gunfire) | Semi-automatic pistol and shotgun | [182][183]
Virginia Beach shooting | 2019 | Virginia Beach, Virginia | 12 (plus the perp.) | 4 | Semi-automatic pistols | [184]
25  | Monterey Park shooting | 2023 | Monterey Park, California | 11 (plus the perp.) | 9 | Semi-automatic pistol | [185][186]
Jacksonville shooting | 1990 | Jacksonville, Florida | 11 (plus the perp.) | 6 | Semi-automatic carbine and revolver | [187]
Pittsburgh synagogue shooting | 2018 | Pittsburgh, Pennsylvania | 11 | 6 (plus the perp.) | Semi-automatic rifle and pistols | [188]
Easter Sunday Massacre | 1975 | Hamilton, Ohio | 11 | 0 | Semi-automatic pistols and revolver | [189]
29  | Santa Fe High School shooting | 2018 | Santa Fe, Texas | 10 | 13 (plus the accused) | Pump-action shotgun and revolver | [190]
Geneva County shootings | 2009 | Geneva County, Alabama | 10 (plus the perp.) | 6 | Semi-automatic rifles, revolver, and shotgun | [191][192]
Buffalo supermarket shooting | 2022 | Buffalo, New York | 10 | 3 | Semi-automatic rifle | [193]
Boulder shooting | 2021 | Boulder, Colorado | 10 | 1 (plus the perp.)[fn 9] | Semi-automatic pistols | [194][195]
Palm Sunday massacre | 1984 | New York City, New York | 10 | 0 | Semi-automatic pistol, revolver | [196]

## See also

[edit]

* Law portal
* Politics portal
* Medicine portal
* United States portal

* List of school massacres by death toll
* Gun laws in the United States
* Gun laws in the United States by state
* Gun violence in the United States
* List of rampage killers in the United States
* School shootings in the United States
* List of school shootings in the United States (before 2000)
* List of school shootings in the United States (2000–present)
* Spree killer
* Public opinion on gun control in the United States
* List of mass shootings in the United States in 2025

## Explanatory notes

[edit]

1. ^ includes 2 victims who in 2019 and 2020 succumbed to injuries from the shooting
2. ^ a b c d e The fatality total includes an unborn child.
3. ^ includes a victim who in 2020 succumbed to the injuries suffered in the shooting
4. ^ Includes a victim who succumbed to his injuries in 2001.
5. ^ Two other victims were killed by stabbing
6. ^ Includes a victim who succumbed to her injuries in 2025.
7. ^ During the massacre, the perpetrators used three .22 caliber handguns of an unknown type that were never recovered by the authorities.
8. ^ One of the victims was killed by stray police gunfire
9. ^ The civilian injury was indirect

## References

[edit]

1. ^ 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."
2. ^ 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."
3. ^ a b c 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."
4. ^ a b c d e Christensen, Jen (October 5, 2017). "Why the US has the most mass shootings". CNN. Retrieved November 6, 2017.
5. ^ 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.
6. ^ Fisher, Max; Keller, Josh (November 7, 2017). "Why Does the U.S. Have So Many Mass Shootings? Research Is Clear: Guns". The New York Times. ISSN 0362-4331. Retrieved November 27, 2022.
7. ^ a b c d e f g Smart, Rosanna; Schell, Terry L. (April 15, 2021). "1. Mass Shootings in the United States". In Ramchand, Rajeev; Saunders, Jessica (eds.). Contemporary Issues in Gun Policy: Essays from the RAND Gun Policy in America Project (PDF) (Report). Santa Monica, CA: RAND Corporation. pp. 1–25. Retrieved March 27, 2023.
8. ^ a b Active Shooter Incidents in the United States in 2021 (Report). Washington, D.C.: Federal Bureau of Investigation/U.S. Department of Justice/Advanced Law Enforcement Rapid Response Training at Texas State University. 2022. Retrieved January 8, 2023.
9. ^ Palazzolo, Joe; Flynn, Alexis (October 3, 2015). "U.S. Leads World in Mass Shootings". The Wall Street Journal. Retrieved October 2, 2017.
10. ^ Healy, Melissa (August 24, 2015). "Why the U.S. is No. 1 – in mass shootings". Los Angeles Times. Retrieved October 2, 2017.
11. ^ a b Michaels, Samantha (August 23, 2015). "The United States Has Had More Mass Shootings Than Any Other Country". Mother Jones. Retrieved October 2, 2017.
12. ^ Fox, Kara (March 9, 2018). "How US gun culture compares with the world in five charts". CNN.
13. ^ a b c d Wallace, Lacey (March 30, 2021). "Mass shootings are rare – firearm suicides are much more common, and kill more Americans". PBS NewsHour. WETA. Retrieved March 20, 2022.
14. ^ 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."
15. ^ Jon Greenberg, Joe Biden said mass shootings tripled when the assault weapon ban ended. They did, PolitiFact (May 25, 2022).
16. ^ "General Methodology". Gun Violence Archive. Retrieved February 21, 2018.
17. ^ Booty, Marisa; O'Dwyer, Jayne; Webster, Daniel; McCourt, Alex; Crifasi, Cassandra (December 3, 2019). "Describing a "mass shooting": the role of databases in understanding burden". Injury Epidemiology. 6 (47): 47. doi:10.1186/s40621-019-0226-7. PMC 6889601. PMID 31828004.
18. ^ Nichols, Chris (October 4, 2017). "How is a 'mass shooting' defined?". PolitiFact California. Retrieved February 21, 2018.
19. ^ "The Mental Health Impact of Mass Shootings" (PDF). Brady: United Against Gun Violence. "Brady defines a mass shooting as a shooting incident in which four or more people, other than the shooter, are shot. Brady uses this definition so as not to "exclude, set apart, caveat, or differentiate victims based upon the circumstances in which they were shot.""
20. ^ "About the Mass Shooting Tracker". Mass Shooting Tracker. Retrieved June 12, 2022.
21. ^ a b "FAQ". Mass Shooting Tracker. Retrieved June 12, 2022.
22. ^ "H.R. 2076 (112th): Investigative Assistance for Violent Crimes Act of 2012". govtrack.us. United States Congress. Retrieved February 20, 2018. "the term mass killings means 3 or more killings in a single incident"
23. ^ 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."
24. ^ 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."
25. ^ a b c "Mass Shootings in America". Everytown for Gun Safety. 2022.
26. ^ 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.
27. ^ a b "US Mass Shootings, 1982–2022: Data From Mother Jones' Investigation". Mother Jones. Retrieved June 12, 2022.
28. ^ Follman, Mark; Aronsen, Gavin; Pan, Deanna (June 9, 2022). "A Guide to Mass Shootings in America". Mother Jones.
29. ^ a b c d e Public Mass Shootings: Database Amasses Details of a Half Century of U.S. Mass Shootings with Firearms, Generating Psychosocial Histories, National Institute of Justice/The Violence Project (February 3, 2022).
30. ^ Follman, Mark (December 3, 2015). "How Many Mass Shootings Are There, Really?". The New York Times. Retrieved December 6, 2015.
31. ^ 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.
32. ^ a b Mark Hay (August 29, 2016). "What Makes a Shooting a Mass Shooting?". Vice.
33. ^ Lopez, German (May 26, 2022). "America's Gun Problem". The New York Times. Archived from the original on May 26, 2022. "Source: Jason R. Silva, William Paterson University"
34. ^ Buchanan, Larry; Leatherby, Lauren (June 22, 2022). "Who Stops a 'Bad Guy With a Gun'?". The New York Times. Archived from the original on June 22, 2022. "Data source: Advanced Law Enforcement Rapid Response Training Center"
35. ^ 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.
36. ^ "Past Summary Ledgers". Gun Violence Archive. May 13, 2022. Retrieved May 15, 2022.
37. ^ Ahmed, Saeed (May 15, 2022). "It's 19 weeks into the year and America has already seen 198 mass shootings". NPR. Retrieved May 15, 2022.
38. ^ "FBI Designates 61 Active Shooter Incidents in 2021" (Press Release) (Press release). FBI National Press Office. May 23, 2022. Retrieved June 3, 2022.
39. ^ "Number of mass shootings in the U.S. 1982-2022".
40. ^ "Behind the Bloodshed". USA Today. Retrieved December 3, 2015.
41. ^ a b c d Lin, Ping-I; Fei, Lin; Barzman, Drew; Hossain, M. (2018). "What have we learned from the time trend of mass shootings in the U.S.?". PLOS One. 13 (10). PLOS: e0204722. Bibcode:2018PLoSO..1304722L. doi:10.1371/journal.pone.0204722. PMC 6193640. PMID 30335790.
42. ^ Kaste, Martin (March 15, 2018). "Despite Heightened Fear Of School Shootings, It's Not A Growing Epidemic". Morning Edition. NPR. Retrieved December 2, 2022.
43. ^ 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.
44. ^ Follman, Mark; Aronsen, Gavin; Pan, Deanna. "US mass shootings, 1982–2022: Data from Mother Jones' investigation". Mother Jones. Retrieved August 5, 2022.
45. ^ "Most Comprehensive Mass Shooter Database". The Violence Project. Retrieved December 24, 2022.
46. ^ a b Barnard, Leslie M.; Wright-Kelly, Erin; Brooks-Russell, Ashley; Betz, Marian E. (July 26, 2023). "Characterization of Mass Shootings by State, 2014-2022". JAMA Network Open. 6 (7): e2325868. doi:10.1001/jamanetworkopen.2023.25868. ISSN 2574-3805. PMC 10372703. PMID 37494046.
47. ^ 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"
48. ^ Statista Research Department (March 2, 2022). "Mass shootings by shooter's race in the U.S. 2021". Statista. Retrieved May 15, 2022.
49. ^ a b 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"
50. ^ "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% of the shooters, the database shows."
51. ^ a b 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."
52. ^ Engber, Daniel (October 6, 2017). "What the white mass-shooter myth gets right and wrong about killers' demographics". Slate Magazine. The Slate Group. Retrieved January 5, 2022. "that figure, too, wasn't that far off from U.S. demographics"
53. ^ a b c Blair, J. Pete; Schweit, Katherine W. (2014). A Study of Active Shooter Incidents, 2000–2013 (Report). Washington, D.C.: Texas State University/Federal Bureau of Investigation, U.S. Justice Department. Retrieved August 18, 2021.
54. ^ a b c Gill, Paul; Horgan, John; Deckert, Paige (2014). "Bombing Alone: Tracing the Motivations and Antecedent Behaviors of Lone-Actor Terrorists". Journal of Forensic Sciences. 59 (2). Wiley-Blackwell: 425–435\. doi:10.1111/1556-4029.12312. PMC 4217375. PMID 24313297.
55. ^ a b Mascia, Jennifer; Brownlee, Chip (April 9, 2024). "The Armed Era". The Trace. Archived from the original on April 14, 2024.
56. ^ Fox, Kara; Shveda, Krystina; Croker, Natalie; Chacon, Marco (November 26, 2021). "How US gun culture stacks up with the world". CNN. Archived from the original on November 26, 2021. "CNN's attribution: Developed countries are defined based on the UN classification, which includes 36 countries. Source: Institute for Health Metrics and Evaluation (Global Burden of Disease 2019), Small Arms Survey (Civilian Firearm Holdings 2017)"
57. ^ Follman, Mark; Aronsen, Gavin; Pan, Deanna. "US Mass Shootings, 1982–2023: Data From Mother Jones' Investigation". Mother Jones. Archived from the original on March 31, 2023. Retrieved March 31, 2023.
58. ^ Follman, Mark; Aronsen, Gavin; Pan, Deanna (2012). "A Guide to Mass Shootings in America". MotherJones.com. Archived from the original on March 10, 2023. "Updated March 27, 2023." Describes inclusion criteria.
59. ^ a b Frankel, Todd C.; Boburg, Shawn; Dawsey, Josh; Parker, Ashley; Horton, Alex (March 27, 2023). "The gun that divides a nation". The Washington Post. Archived from the original on March 27, 2023. Frankel et al. credit: "Source: National Shooting Sports Foundation and Bureau of Alcohol, Tobacco, Firearms and Explosives." Frankel et al. quote: "The shift began after the 2004 expiration of a federal assault weapons ban that had blocked the sales of many semiautomatic rifles. A handful of manufacturers saw a chance to ride a post-9/11 surge in military glorification while also stoking a desire among new gun owners to personalize their weapons with tactical accessories."
60. ^ a b c d Healy, Melissa (August 24, 2015). "Why the U.S. is No. 1 – in mass shootings". Los Angeles Times. Retrieved November 6, 2017.
61. ^ DiMaggio, Charles; Avraham, Jacob; Berry, Cherisse; Bukur, Marko; Feldman, Justin; Klein, Michael; Shah, Noor; Tandon, Manish; Frangos, Spiros (2019). "Changes in US mass shooting deaths associated with the 1994-2004 federal assault weapons ban: Analysis of open-source data". The Journal of Trauma and Acute Care Surgery. 86 (1). Lippincott Williams & Wilkins: 11–19\. doi:10.1097/TA.0000000000002060. PMID 30188421.
62. ^ Schuppe, Jon (May 14, 2023). "What makes the AR-15 so beloved and so reviled". NBC News.
63. ^ Smart, Rosanna (January 10, 2023). Effects of Assault Weapon and High-Capacity Magazine Bans on Mass Shootings (Report). RAND Corporation. Retrieved February 13, 2024.
64. ^ Gius, Mark (2015). "The Impact of State and Federal Assault Weapons Bans on Public Mass Shootings". Applied Economics Letters. 22 (4). Routledge: 281–284\. doi:10.1080/13504851.2014.939367.
65. ^ Blau, Benjamin M.; Gorry, Devon H.; Wade, Chip (2016). "Guns, Laws, and Public Shootings in the United States". Applied Economics. 48 (49). Routledge: 4732–4746\. doi:10.1080/00036846.2016.1164821.
66. ^ Luca, Michael; Malhotra, Deepak; Poliquin, Christopher (2016). The Impact of Mass Shootings on Gun Policy (PDF) (Report). Boston, MA: Harvard Business School. SSRN 2776657. 16-126. Retrieved February 13, 2024.
67. ^ Gius, Mark (2018). "The Effects of State and Federal Gun Control Laws on School Shootings". Applied Economics Letters. 25 (5). Routledge: 317–320\. doi:10.1080/13504851.2017.1319555.
68. ^ Klarevas, Louis; Conner, Andrew; Hemenway, David (2019). "The Effect of Large-Capacity Magazine Bans on High-Fatality Mass Shootings, 1990–2017". American Journal of Public Health. 109 (12). American Public Health Association: 1754–1761\. doi:10.2105/AJPH.2019.305311. PMC 6836798. PMID 31622147.
69. ^ Webster, Daniel W.; McCourt, Alexander D.; Crifasi, Cassandra K.; Booty, Marisa D.; Stuart, Elizabeth A. (2020). "Evidence Concerning the Regulation of Firearms Design, Sale, and Carrying on Fatal Mass Shootings in the United States". Criminology & Public Policy. 19 (1). Wiley: 171–212\. doi:10.1111/1745-9133.12487.
70. ^ [64][65][66][67][68][69]
71. ^ Todd, Michael (December 23, 2013). "The Simple Facts About Mass Shootings Aren't Simple at All". Pacific Standard. Retrieved August 21, 2018.
72. ^ James Alan Fox; Emma E. Fridel (2016). "The Tenuous Connections Involving Mass Shootings, Mental Illness, and Gun Laws". Violence and Gender. 3 (10): 14–19\. doi:10.1089/vio.2015.0054.
73. ^ 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."
74. ^ a b Glenn Thrush (May 16, 2022). "What Do Most Mass Shooters Have in Common? They Bought Their Guns Legally". New York Times.
75. ^ "The facts on mass shootings, guns in the United States". PolitiFact. May 18, 2018. Retrieved June 11, 2018.
76. ^ Pearce, Matt (February 14, 2018). "Mass shootings are getting deadlier. And the latest ones all have something new in common: The AR-15". Los Angeles Times. Retrieved May 11, 2018.
77. ^ a b Towers, Sherry; Gomez-Lievano, Andres; Khan, Maryam; Mubayi, Anuj; Castillo-Chavez, Carlos (2015). "Contagion in Mass Killings and School Shootings". PLOS ONE. 1 (7): e0117259. Bibcode:2015PLoSO..1017259T. doi:10.1371/journal.pone.0117259. PMC 4489652. PMID 26135941.
78. ^ a b Reeping, Paul M; Cerdá, Magdalena; Kalesan, Bindu; Wiebe, Douglas J; Galea, Sandro; Branas, Charles C (2019). "State gun laws, gun ownership, and mass shootings in the US: cross sectional time series". The BMJ. 364: l542. doi:10.1136/bmj.l542. PMC 6402045. PMID 30842105.
79. ^ a b Siegel, Michael; Goder-Reiser, Max; Duwe, Grant; Rocque, Michael; Fox, James Alan; Fridel, Emma E. (2020). "The relation between state gun laws and the incidence and severity of mass public shootings in the United States, 1976–2018". Law and Human Behavior. 44 (5). American Psychology–Law Society: 347–360\. doi:10.1037/lhb0000378. PMID 33090863.
80. ^ a b c "Op-Ed: We have studied every mass shooting since 1966. Here's what we've learned about the shooters", Los Angeles Times, August 4, 2019
81. ^ a b "Shooting Data & Research". The Violence Project. National Institute of Justice. Retrieved June 9, 2022.
82. ^ a b c d e Pan, Deanna (June 3, 2022). "What drives mass shooters? Grievance, despair, and anger are more likely triggers than mental illness, experts say". The Boston Globe. Retrieved June 5, 2022.
83. ^ Vestal, Christine (August 8, 2019). "One-Third of Mass Shootings Committed by People With Mental Illness, Study Says". The Pew Charitable Trusts.
84. ^ "APA Condemns Loss of Life from Gun Violence, Disputes Link to Mental Illness". www.psychiatry.org. Retrieved December 29, 2021.
85. ^ "Statement of APA CEO on Gun Violence and Mental Health". www.apa.org. August 5, 2019. Retrieved December 29, 2021.
86. ^ Brucato, Gary; Appelbaum, Paul S.; Hesson, Hannah; Shea, Eileen A.; Dishy, Gabriella; Lee, Kathryn; Pia, Tyler; Syed, Faizan; Villalobos, Alexandra; Wall, Melanie M.; Lieberman, Jeffrey A.; Girgis, Ragy R. (2021). "Psychotic symptoms in mass shootings v. mass murders not involving firearms: findings from the Columbia mass murder database". Psychological Medicine. 52 (15). Cambridge University Press: 1–9\. doi:10.1017/S0033291721000076. PMID 33595428. S2CID 231944742. Retrieved August 16, 2021.
87. ^ Ramsland, Katherine (February 26, 2021). "Is There a Link Between Madness and Mass Murder?". Psychology Today. Sussex Publishers. Retrieved August 16, 2021.
88. ^ "Researchers Issue First Report on Mass Shootings from the Columbia Mass Murder Database" (Press release). Columbia University Irving Medical Center. February 18, 2021. Retrieved August 17, 2021.
89. ^ Twenge, Jean; Campbell, W. Keith (2010). The Narcissism Epidemic: Living in the Age of Entitlement. New York: Atria Publishing Group. pp. 199–200\. ISBN 978-1-4165-7599-3.
90. ^ Pinker, Steven (2011). The Better Angels of Our Nature: Why Violence Has Declined. New York: Penguin Books. pp. 519–521\. ISBN 978-0-14-312201-2.
91. ^ Langman, Peter F. (2021). Warning Signs: Identifying School Shooters Before They Strike. Allentown, PA: Langman Psychological Associates. ISBN 978-0-578-92299-7.
92. ^ Silver, James; Simons, Andre; Craun, Sarah (2018). A Study of Pre-Attack Behaviors of Active Shooters in the United States Between 2000 and 2013 (Report). Washington, D.C.: Federal Bureau of Investigation, U.S. Justice Department. Retrieved June 5, 2022.
93. ^ Pies, Ronald W. (February 17, 2020). "Mass Shooters and the Psychopathology Spectrum". Psychiatric Times. MJH Associates. Retrieved August 17, 2021.
94. ^ Peterson, Jillian K.; Densley, James A.; Knapp, Kyle; Higgins, Stasia; Jensen, Amanda (2022). "Psychosis and Mass Shootings: A Systematic Examination Using Publicly Available Data". Psychology, Public Policy, and Law. 28 (2). American Psychological Association: 280–291\. doi:10.1037/LAW0000314. S2CID 235565400.
95. ^ Vossekuil, Bryan; Fein, Robert A.; Reddy, Marisa; Borum, Randy; Modzeleski, William (2004). The Final Report and Findings of the Safe School Initiative: Implications for the Prevention of School Attacks in the United States (PDF) (Report). U.S. Secret Service/U.S. Department of Education. Retrieved June 9, 2022.
96. ^ a b Lankford, A; Silver, J.; Cox, J. (2021). "An epidemiological analysis of public mass shooters and active shooters: Quantifying key differences between perpetrators and the general population, homicide offenders, and people who die by suicide". Journal of Threat Assessment and Management. 8 (4). Association of Threat Assessment Professionals: 125–144\. doi:10.1037/tam0000166. S2CID 240508009.
97. ^ a b c Vitelli, Romeo (January 31, 2022). "Can Mass Shootings Be Prevented?". Psychology Today. Sussex Publishers. Retrieved June 9, 2022.
98. ^ a b Koerth, Maggie (June 6, 2022). "Suicide Prevention Could Prevent Mass Shootings". FiveThirtyEight. Retrieved June 9, 2022.
99. ^ a b Girgis, Ragy R.; Rogers, Russell Tyler; Hesson, Hannah; Lieberman, Jeffrey A.; Appelbaum, Paul S.; Brucato, Gary (2022). "Mass murders involving firearms and other methods in school, college, and university settings: Findings from the Columbia Mass Murder Database". Journal of Forensic Sciences. 68 (1). Wiley-Blackwell: 207–211\. doi:10.1111/1556-4029.15161. ISSN 0022-1198. PMID 36303265.
100. ^ a b Cantor, Carla (October 28, 2022). "New Findings from the Columbia Mass Murder Database" (Press release). Columbia University Department of Psychiatry. Retrieved February 13, 2024.
101. ^ a b Koerth, Maggie (August 22, 2019). "Can We Prevent Mass Shootings By Preventing Suicide?". FiveThirtyEight. Retrieved June 9, 2022.
102. ^ a b Jillian Peterson; Gina Erickson; Kyle Knapp; James Densley (November 4, 2021), "Communication of Intent to Do Harm Preceding Mass Public Shootings in the United States, 1966 to 2019", JAMA Network Open, 4 (11)
103. ^ Geller, Lisa B.; Booty, Marisa; Crifasi, Cassandra K. (May 31, 2021). "The role of domestic violence in fatal mass shootings in the United States, 2014–2019". Injury Epidemiology. 8 (1): 38. doi:10.1186/s40621-021-00330-0. ISSN 2197-1714. PMC 8165999. PMID 34053458.
104. ^ Saad, Lydia (November 13, 2020). "What Percentage of Americans Own Guns?". Gallup.
105. ^ Fry, Richard; Passel, Jeffrey S.; Cohn, D'Vera (October 12, 2021). "U.S. household growth over last decade was the lowest ever recorded". Pew Research Center. Retrieved February 13, 2024.
106. ^ Ogunwole, Stella U.; Rabe, Megan A.; Roberts, Andrew W.; Caplan, Zoe (August 12, 2021). "Adult Population Grew Faster Than Total Population From 2010 to 2020: Population Under Age 18 Declined Last Decade" (Press release). United States Census Bureau. Retrieved April 25, 2024.
107. ^ a b c Boschma, Janie; Merrill, Curt; Murphy-Teixidor, John (October 4, 2023). "Mass Shootings in the US Fast Facts". CNN. Retrieved February 13, 2024.
108. ^ "Mental Illness – Statistics". National Institute of Mental Health. Retrieved February 13, 2024.
109. ^ Swanson, Jeffrey W. (2018). "Redirecting the Mental Health and Gun Violence Conversation From Mass Shootings to Suicide". Psychiatric Services. 69 (12). American Psychiatric Association: 1198–1199\. doi:10.1176/appi.ps.201800365.
110. ^ "Suicides in the U.S. reached all-time high in 2022, CDC data shows". NBC News. Associated Press. August 10, 2023. Retrieved August 11, 2023.
111. ^ Wernau, Julie (November 29, 2023). "U.S. Suicides Reached a Record High Last Year". The Wall Street Journal. News Corp. Retrieved February 13, 2024.
112. ^ Cohn, D'Vera; Passel, Jeffrey S.; Wang, Wendy; Livingston, Gretchen (December 14, 2011). "Barely Half of U.S. Adults Are Married – A Record Low". Pew Research Center. Retrieved February 15, 2020.
113. ^ Parker, Kim; Stepler, Renee (September 14, 2017). "As U.S. marriage rate hovers at 50%, education gap in marital status widens". Pew Research Center. Retrieved April 6, 2023.
114. ^ Wang, Wendy; Parker, Kim (September 24, 2014). "Record Share of Americans Have Never Married". Pew Research Center. Retrieved February 15, 2020.
115. ^ Fry, Richard (October 11, 2017). "The share of Americans living without a partner has increased, especially among young adults". Pew Research Center. Retrieved February 15, 2020.
116. ^ Ortiz-Ospina, Esteban; Roser, Max (December 7, 2017). "Marriages and Divorces". Our World in Data. Global Change Data Lab. Retrieved April 4, 2023.
117. ^ Putnam, Robert D. (2000). Bowling Alone: The Collapse and Revival of American Community. New York: Simon & Schuster. pp. 277. ISBN 978-0684832838.
118. ^ Tanzi, Alexandre (December 3, 2021). "U.S. Married Couple Households With Children Fall to Record Low". Bloomberg News. Bloomberg L.P. Retrieved April 6, 2023.
119. ^ "National Statistics". NCADV. National Coalition Against Domestic Violence. Archived from the original on May 27, 2019. Retrieved October 5, 2018.
120. ^ "Mass Shootings in 2025". Gun Violence Archive.
121. ^ Gramlich, John (February 3, 2022). "What the data says about gun deaths in the U.S." Pew Research Center. Retrieved January 21, 2023.
122. ^ Knoll, James L.; Annas, George D. (2015). "4. Mass Shootings and Mental Illness". In Gold, Liza H.; Simon, Robert I. (eds.). Gun Violence and Mental Illness. New York: American Psychiatric Association. pp. 91–94\. ISBN 978-1-58562-498-0.
123. ^ Dorell, Oren (December 18, 2012). "In Europe, fewer mass killings due to culture not guns". USA Today. Retrieved August 11, 2015.
124. ^ a b Kwon, Roy; Cabrera, Joseph F. (2019). "Social integration and mass shootings in U.S. counties". Journal of Crime & Justice. 42 (2). Routledge: 121–139\. doi:10.1080/0735648X.2018.1510336.
125. ^ Szendrő, Brendan (2022). "Community, faith, and public violence: A county-level examination of religious institutions and mass public shootings in the United States". Journal of Crime & Justice. 45 (4). Routledge: 467–483\. doi:10.1080/0735648X.2021.1990786.
126. ^ Putnam, Robert D. (2000). Bowling Alone: The Collapse and Revival of American Community. New York: Simon & Schuster. pp. 204–215, 287–295, 307–318\. ISBN 978-0-684-83283-8.
127. ^ Putnam, Robert D. (2000). Bowling Alone: The Collapse and Revival of American Community. New York: Simon & Schuster. pp. 15–284, 217, 252–253, 275. ISBN 978-0-684-83283-8.
128. ^ Putnam, Robert D. (May 31, 2000). "Going Bowling". All Things Considered (Interview). Interviewed by Robert Siegel. NPR. Retrieved December 7, 2022.
129. ^ Putnam, Robert D. (November 10, 2020). "How U.S. history could provide a path out of polarization". PBS NewsHour (Interview). Interviewed by Paul Solman. WETA. Retrieved December 7, 2022.
130. ^ Putnam, Robert D. (2020). Bowling Alone: The Collapse and Revival of American Community (2nd ed.). New York: Simon & Schuster. pp. 415–444\. ISBN 978-1-9821-3084-8.
131. ^ Putnam, Robert D. (2000). Bowling Alone: The Collapse and Revival of American Community. New York: Simon & Schuster. pp. 22–24, 166–180, 217. ISBN 978-0-684-83283-8.
132. ^ Putnam, Robert D. (March 15, 2022). "Politics And America's Loneliness Epidemic" (Interview). Interviewed by Danielle Kurtzleben. NPR. Retrieved December 7, 2022.
133. ^ Derosa, Anthony (April 17, 2021). "Indianapolis FedEx Shooting: Brandon Hole, the Victims, What We Know". Wall Street Journal.
134. ^ "Key Findings - Comprehensive Mass Shooter Data". The Violence Project. National Institute of Justice. Retrieved June 10, 2022.
135. ^ Pinker, Steven (2018). Enlightenment Now: The Case for Reason, Science, Humanism, and Progress. New York: Viking Press. pp. 39–52\. ISBN 978-0-525-42757-5.
136. ^ Burgess, Ann Wolbert; Garbarino, Christina; Carlson, Mary I. (2006). "Pathological teasing and bullying turned deadly: Shooters and suicide". Victims and Offenders. 1 (1): 1–14\. doi:10.1080/15564880500498705. S2CID 144987837.
137. ^ Reese, Phillip (October 7, 2019). "When masculinity turns 'toxic': A gender profile of mass shootings". Los Angeles Times. Retrieved June 25, 2022.
138. ^ Johnson, Kevin (November 9, 2017). "Texas Church Shooting Background Check Failure". USA Today. Retrieved November 17, 2017.
139. ^ Barrett, Devlin (November 10, 2017). "FBI's Gun Background Check Database Missing Records". Chicago Tribune. Retrieved November 17, 2017.
140. ^ Wolff, Richard D.; Fraad, Harriet (November 8, 2017). "American hyper-capitalism breeds the lonely, alienated men who become mass killers". Salon. Retrieved August 5, 2019.
141. ^ Kwon, Roy; Cabrera, Joseph F. (September 20, 2019). "Income inequality and mass shootings in the United States". BMC Public Health. 19 (1): 1147. doi:10.1186/s12889-019-7490-x. PMC 6753615. PMID 31537201. "There is strong evidence in this study to suggest the recent growth of income inequality is significantly associated with mass shootings in the United States. Specifically, this evidence indicates that a one standard deviation increase in the growth of income inequality augments the number of mass shootings by 0.43 to 0.57."
142. ^ a b c Newman, Benjamin J.; Hartman, Todd K. (2019). "Mass Shootings and Public Support for Gun Control". British Journal of Political Science. 49 (4): 1527–1553\. doi:10.1017/S0007123417000333.
143. ^ a b c Barney, David J; Schaffner, Brian F (2019). "Reexamining the Effect of Mass Shootings on Public Support for Gun Control". British Journal of Political Science. 49 (4): 1555–1565\. doi:10.1017/S0007123418000352. S2CID 159183682.
144. ^ a b Hassell, Hans; Holbein, John; Baldwin, Matthew (2020). "Mobilize for Our Lives? School Shootings and Democratic Accountability in U.S. Elections". American Political Science Review. 114 (4): 1375–1385\. doi:10.1017/S0003055420000635. S2CID 225118870.
145. ^ a b García-Montoya, Laura; Arjona, Ana; Lacombe, Matthew (2021). "Violence and Voting in the United States: How School Shootings Affect Elections". American Political Science Review. 116 (3): 807–826\. doi:10.1017/S0003055421001179. ISSN 0003-0554. S2CID 243948104.
146. ^ Hassell, Hans J. G.; Holbein, John B. (February 2025). "Navigating Potential Pitfalls in Difference-in-Differences Designs: Reconciling Conflicting Findings on Mass Shootings' Effect on Electoral Outcomes". American Political Science Review. 119 (1): 240–260\. doi:10.1017/S0003055424000108. ISSN 0003-0554.
147. ^ a b Patrick Sharkey & Yinzhi Shen (2021). "The effect of mass shootings on daily emotions is limited by time, geographic proximity, and political affiliation". Proceedings of the National Academy of Sciences of the United States of America. 118 (23): e2100846118. Bibcode:2021PNAS..11800846S. doi:10.1073/pnas.2100846118. PMC 8202016. PMID 34074780.
148. ^ 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.
149. ^ 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.
150. ^ 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.
151. ^ a b Sarah R. Lowe & Sandro Galea (2017). "The Mental Health Consequences of Mass Shootings". Trauma, Violence, & Abuse. 18 (1): 62–82\. doi:10.1177/1524838015591572. PMID 26084284. S2CID 43451895.
152. ^ a b Czaja, Matthew P.; Kraus, Chadd K.; Phyo, Su; Olivieri, Patrick; Mederos, Dalier R.; Puente, Ivan; Mohammed, Salman; Berkeley, Ross P.; Slattery, David; Gildea, Thomas H.; Hardman, Claire; Palmer, Brandi (2023). "Nonfatal Injuries Sustained in Mass Shootings in the US, 2012–2019: Injury Diagnosis Matrix, Incident Context, and Public Health Considerations". Western Journal of Emergency Medicine. 24 (3): 562. doi:10.5811/westjem.58395. PMC 10284525. PMID 37278791.
153. ^ "Deadliest Mass Shootings in Modern US History Fast Facts". CNN. April 1, 2018. Retrieved April 6, 2018.
154. ^ a b c d e f g h i "Deadliest Mass Shootings in Modern US History Fast Facts". CNN. Retrieved November 5, 2017.
155. ^ a b c d e Blau, Reuven (November 6, 2017). "Texas gunman used same rifle as Las Vegas, Newtown mass shooters". New York Daily News. Retrieved November 7, 2017.
156. ^ Holly Yan; Madison Park (October 3, 2017). "Las Vegas shooting: Bodycam footage shows first response". CNN. Retrieved April 18, 2020.
157. ^ Carissimo, Justin (November 6, 2017). "26 dead in shooting at church in Sutherland Springs, Texas". CBS News. Retrieved November 6, 2017.
158. ^ Blankstein, Andrew; Burke, Minyvonne (August 3, 2019). "El Paso shooting: 20 people dead, at least 26 injured, suspect in custody, police say". NBC News. Retrieved August 3, 2019.
159. ^ Maxouris, Christina; Andone, Dakin; Chavez, Nicole; Levenson, Eric (August 5, 2019). "El Paso shooting death toll rises to 22 in anti-immigrant massacre". CNN. Retrieved August 5, 2019.
160. ^ "El Paso Shooting Victim Dies Months Later, Death Toll Now 23". The New York Times. April 26, 2020. Retrieved April 26, 2020.
161. ^ "Texas Man Pleads Guilty to 90 Federal Hate Crimes and Firearms Violations for August 2019 Mass Shooting at Walmart in el Paso, Texas". February 8, 2023.
162. ^ Garcia, Eugene; Lopez-Mills, Dario (May 24, 2022). "Texas governor: 15 killed in school shooting; gunman dead". Associated Press. Retrieved May 24, 2022.
163. ^ "18 students, 3 adults killed in Uvalde school shooting; suspect dead". Dallas News. May 25, 2022. Retrieved May 25, 2022.
164. ^ Sharp, David; Bumsted, Robert; Ramer, Holly; Balsamo, Michael (October 26, 2023). "Fearful Maine residents stay home amid massive search for suspect in killing of 18 people". Associated Press. Lewiston, Maine. Archived from the original on October 26, 2023. Retrieved October 26, 2023.
165. ^ "18 killed, 13 injured in Maine mass shooting as police hunt for gunman". CBS News. October 27, 2023. Retrieved October 27, 2023.
166. ^ Grinberg, Emanuella; Levensen, Eric (February 14, 2018). "At least 17 dead in Florida school shooting, law enforcement says". CNN. Retrieved February 14, 2018.
167. ^ Cole, Matthew; Thomas, Pierre; Ryan, Jason; Esposito, Richard (November 19, 2009). "'Cop Killer' Gun Used In Ft. Hood Shooting, Officials Said". ABC News. Retrieved October 30, 2018.
168. ^ Carter, Chelsea J. (August 23, 2013). "Nidal Hasan convicted in Fort Hood shootings". CNN. Retrieved October 30, 2018.
169. ^ "Columbine killer has cult of fans long after death". New York Post. February 24, 2016. Retrieved October 29, 2018.
170. ^ Castillo, Michelle (July 20, 2012). "Colo. shooter purchased guns legally from 3 different stores". CBS News. Retrieved October 30, 2018.
171. ^ Jacobo, Julia (July 21, 2017). "A look back at the Aurora, Colorado, movie theater shooting 5 years later". ABC News. Retrieved October 30, 2018.
172. ^ "Remembering 12 killed in Aurora theater shooting". Denver 7 Colorado News (KMGH). July 20, 2018. Retrieved February 11, 2025.
173. ^ McFadden, Robert D. (April 3, 2009). "Gunman Kills 13 and Wounds 4 at Binghamton, N.Y., Immigrant Center". The New York Times. Retrieved October 30, 2018.
174. ^ Berger, Meyer (September 7, 1949). "Veteran Kills 12 in Mad Rampage on Camden Street". The New York Times. Retrieved July 6, 2018. "Howard B. Unruh, 28 years old, a mild, soft-spoken veteran of many armored artillery battles in Italy, France, Austria, Belgium and Germany, killed twelve persons with a war souvenir Luger pistol in his home block in East Camden this morning. He wounded four others."
175. ^ Sauer, Patrick (October 14, 2015). "The Story of the First Mass Murder in U.S. History". Smithsonian Magazine. Smithsonian Institution. "He went into his apartment, uncased his German Luger P08, a 9mm pistol he'd purchased at a sporting goods store in Philadelphia for $37.50, and secured it with two clips and 33 loose cartridges."
176. ^ Banks v. Horn,  99-9005 (United States Court of Appeals for the Third Circuit October 31, 2001) ("On September 25, 1982 in Wilkes-Barre, Pennsylvania, Banks shot fourteen people with a Colt AR-15 semi-automatic rifle, killing thirteen and wounding one.").
177. ^ 513 Pa. 318 (Supreme Court of Pennsylvania 1987) ("In the space of about one hour, appellant shot fourteen people with a Colt AR-15 semi-automatic rifle, killing thirteen and wounding one.").
178. ^ Dietz, P.E. (1986). "Mass, serial and sensational homicides". Bulletin of the New York Academy of Medicine. 62 (5): 477–491\. PMC 1629267. PMID 3461857. "He had purchased equipment and materials of the kind advertised and promoted in these magazines, including a Colt AR-15 semi-automatic rifle..."
179. ^ Kang, Martha (February 26, 2010). "Wah Mee Massacre prisoner closer to release". KOMO News.
180. ^ Cook, James (November 8, 2018). "Gunman kills 12 in California bar". BBC News. Retrieved November 8, 2018.
181. ^ Said-Moorhouse, Lauren; Picheta, Rob; Rocha, Veronica; Wagner, Meg; Yeung, Jessie (November 8, 2018). "Mass shooting at California dance bar". CNN. Retrieved November 8, 2018.
182. ^ Hermann, Peter; Marimow, Ann E. (September 25, 2013). "Navy Yard shooter Aaron Alexis driven by delusions". Washington Post. Retrieved October 30, 2018.
183. ^ Madhani, Aamer (July 2, 2015). "What happened in 2013 Navy Yard mass shooting". USA Today. Retrieved October 30, 2018.
184. ^ Duggan, Paul. "'Suddenly, a kind of hole exploded in my wall.' Pop-pops and then duck for cover". The Washington Post. Retrieved June 3, 2019.
185. ^ Dalton, Andrew (January 22, 2023). "Police: Gunman on the loose after killing 10 near LA". Associated Press. Retrieved January 22, 2023.
186. ^ Winton, Richard; Park, Jeong; Jany, Libor; Lin, Summer; Ellis, Summer (January 22, 2023). "10 people killed, 10 injured in mass shooting at Monterey Park dance studio". Los Angeles Times. Retrieved January 22, 2023.
187. ^ Florida Gunman Kills 8 And Wounds 6 in Office - New York Times. The New York Times (1990-06-19). Retrieved on 2023-06-17.
188. ^ Andone, Dakin; Hanna, Jason; Sterling, Joe; Murphy, Paul P. (October 27, 2018). "Hate crime charges filed in Pittsburgh synagogue shooting that left 11 dead". CNN. Retrieved October 27, 2018.
189. ^ Machi, Vivienne (September 24, 2016). "40 years later, Ruppert family murders still traumatic". Dayton Daily News. Archived from the original on March 28, 2018. Retrieved March 27, 2018.
190. ^ Andone, Dakin; Allen, Keith; Almasy, Steve (May 18, 2018). "Alleged shooter at Texas high school spared people he liked, court document says". CNN. Retrieved May 18, 2018.
191. ^ Osunsami, Steve; Carter, Bill; Mooney, Mark; Mcguirt, Mary; Schabner, Dean (March 12, 2009). "Cops Close to Motive in Murderous Rampage". ABC News. Retrieved October 30, 2018.
192. ^ Dewan, Shaila; Sulzberger, A.G. (March 11, 2009). "Officials Identify Alabama Gunman". The New York Times. Retrieved October 30, 2018.
193. ^ Gee, Derek (May 14, 2022). "Ten killed in mass shooting at Jefferson Avenue supermarket; officials describe attack as 'hate crime'". The Buffalo News. Retrieved May 14, 2022.
194. ^ Vera, Amir (March 22, 2021). "Witnesses describe chaos as shooter opened fire in a Colorado grocery store". CNN. Retrieved March 22, 2021.
195. ^ "Boulder shooting suspect charged with 10 counts of first-degree murder". CNN. March 23, 2021. Archived from the original on March 24, 2021. Retrieved March 23, 2021.
196. ^ McFadden, Robert D. (April 16, 1984). "10 In Brooklyn Are Found Slain Inside A House". The New York Times. Retrieved March 27, 2018.

## Further reading

[edit]

* Oreskes, Naomi, "Furious about Firearms: Outrage, not hope, will move us to prevent gun violence", Scientific American, vol. 329, no. 1 (July/August 2023), p. 96.

## External links

[edit]

Wikiquote has quotations related to Mass shootings in the United States.

* Jetter, Michael; Jay K. Walker (October 2018). "The Effect of Media Coverage on Mass Shootings" (PDF). IZA Institute of Labor Economics.
* Most Comprehensive Mass Shooter Database—The Violence Project
* "Mass Shootings in 2023 | Gun Violence Archive". Gun Violence Archive.

* v
* t
* e

Mass shootings in the United States

List|

* 20th century
* 2000–2009
* 2018
* 2019
* 2020
* 2021
* 2022
* 2023
* 2024
* 2025

Related terms
and topics|

* Active shooter
* Gun violence in the United States
* "'No Way to Prevent This,' Says Only Nation Where This Regularly Happens"
* School shooting
* before 2000
* 2000–present
* by death toll

* v
* t
* e

Deadliest mass shootings in the United States

1. Paradise, NV (2017) (60 deaths)
2. Orlando, FL (2016) (49 deaths)
3. Blacksburg, VA (2007) (32 deaths)
4. Newtown, CT (2012) (27 deaths)
5. Sutherland Springs, TX (2017) (26 deaths)
6. Killeen, TX (1991) (23 deaths)
7. El Paso, TX (2019) (23 deaths)
8. San Diego, CA (1984) (22 deaths)
9. Uvalde, TX (2022) (21 deaths)
10. Lewiston, ME (2023) (18 deaths)
11. Austin, TX (1966) (17 deaths)
12. Parkland, FL (2018) (17 deaths)
13. Fort Hood, TX (2009) (14 deaths)
14. San Bernardino, CA (2015) (14 deaths)
15. Edmond, OK (1986) (14 deaths)
16. Columbine, CO (1999) (14 deaths)
17. Binghamton, NY (2009) (13 deaths)
18. Camden, NJ (1949) (13 deaths)
19. Wilkes-Barre, PA (1982) (13 deaths)
20. Seattle, WA (1983) (13 deaths)
21. Aurora, CO (2012) (12 deaths)
22. Thousand Oaks, CA (2018) (12 deaths)
23. Washington, D.C. (2013) (12 deaths)
24. Virginia Beach, VA (2019) (12 deaths)
25. Monterey Park, CA (2023) (11 deaths)
26. Jacksonville, FL (1990) (11 deaths)
27. Pittsburgh, PA (2018) (11 deaths)
28. Hamilton, OH (1975) (11 deaths)
29. Santa Fe, TX (2018) (10 deaths)
30. Geneva County, AL (2009) (10 deaths)
31. Buffalo, NY (2022) (10 deaths)
32. Boulder, CO (2021) (10 deaths)
33. New York City, NY (1984) (10 deaths)

Death counts do not include deceased perpetrator(s). This navbox reflects information from this list.

* v
* t
* e

School shootings in the United States

Prior to 2000
(full list)|

| 1760s|

* Enoch Brown school massacre (1764)

|

1960s|

* University of Texas (1966)
* Rose-Mar College of Beauty (1966)

1970s|

* Kent State University (1970)
* Jackson State University (1970)
* Olean High School (1974)
* Computer Learning Center (1976)
* California State University, Fullerton (1976)
* Cleveland Elementary School (1979)

1980s|

* 49th Street Elementary School (1984)
* Cokeville Elementary School (1986)
* Hubbard Woods Elementary School (1988)
* Oakland Elementary School (1988)
* Cleveland Elementary School (1989)

1990s|

* University of Iowa (1991)
* Lindhurst High School (1992)
* Bard College at Simon's Rock (1992)
* East Carter High School (1993)
* Wickliffe Middle School (1994)
* Blackville–Hilda High School (1995)
* Richland High School (1995)
* Frontier Middle School (1996)
* San Diego State University (1996)
* Bethel Regional High School (1997)
* Pearl High School (1997)
* Heath High School (1997)
* Westside Middle School (1998)
* Parker Middle School (1998)
* Thurston High School (1998)
* Columbine High School (1999)

2000 to present
(full list)|

| 2000s|

* Buell Elementary School (2000)
* Lake Worth Middle School (2000)
* University of Arkansas (2000)
* Santana High School (2001)
* Appalachian School of Law (2002)
* John McDonogh High School (2003)
* Case Western Reserve University (2003)
* Rocori High School (2003)
* Red Lake Senior High School (2005)
* Campbell County High School (2005)
* Pine Middle School (2006)
* Platte Canyon High School (2006)
* Weston High School (2006)
* West Nickel Mines School (2006)
* Virginia Tech (2007)
* Delaware State University (2007)
* SuccessTech Academy (2007)
* Northern Illinois University (2008)
* E.O. Junior High School (2008)
* University of Central Arkansas (2008)

|

2010s|

* University of Alabama in Huntsville (2010)
* Chardon High School (2012)
* Oikos University (2012)
* Sandy Hook Elementary School (2012)
* Santa Monica College (2013)
* Sparks Middle School (2013)
* University of California, Santa Barbara (2014)
* Marysville Pilchuck High School (2014)
* Florida State University (2014)
* Umpqua Community College (2015)
* Northern Arizona University (2015)
* University of California, Los Angeles (2016)
* El Centro College (2016)
* Townville Elementary School (2016)
* North Park Elementary School (2017)
* Rancho Tehama Elementary School (2017)
* Aztec High School (2017)
* Marshall County High School (2018)
* Stoneman Douglas High School (2018)
* Santa Fe High School (2018)
* Noblesville West Middle School (2018)
* University of North Carolina at Charlotte (2019)
* STEM School Highlands Ranch (2019)
* Saugus High School (2019)

2020s|

* Oxford High School (2021)
* Liberty Point International Middle School (2022)
* East High School (2022)
* Edmund Burke School (2022)
* Robb Elementary School (2022)
* Rusdale High School (2022)
* Central Visual and Performing Arts High School (2022)
* University of Virginia (2022)
* Richneck Elementary School (2023)
* Michigan State University (2023)
* Covenant School (2023)
* Virginia Commonwealth University (2023)
* University of North Carolina at Chapel Hill (2023)
* University of Nevada, Las Vegas (2023)
* Perry High School (2024)
* Apalachee High School (2024)
* Tuskegee University (2024)
* Feather River School (2024)
* Abundant Life Christian School (2024)
* Antioch High School (2025)
* Florida State University (2025)

In media|

| Film and
television|

* The Deadly Tower (1975)
* Detention: The Siege at Johnson High (1997)
* Duck! The Carbine High Massacre (1999)
* Bang Bang You're Dead (2002)
* Bowling for Columbine (2002)
* Heart of America (2002)
* Home Room (2002)
* "Jimmy" (2002)
* Elephant (2003)
* Zero Day (2003)
* American Yearbook (2004)
* "Time Stands Still" (2004)
* The Only Way (2004)
* Dawn Anna (2005)
* All the Boys Love Mandy Lane (2006)
* American Gun (2006)
* State's Evidence (2006)
* The Life Before Her Eyes (2007)
* April Showers (2009)
* Beautiful Boy (2010)
* We Need to Talk About Kevin (2011)
* Hello Herman (2012)
* White Rabbit (2013)
* Rudderless (2014)
* Sins of Our Youth (2014)
* The Cokeville Miracle (2015)
* I'm Not Ashamed (2016)
* Tower (2016)
* "Dead Kids" (2018)
* Vox Lux (2018)
* Safety (2019)
* If Anything Happens I Love You (2020)
* Run Hide Fight (2020)
* The Fallout (2021)
* Mass (2021)
* Eric Larue (2023)
* The Graduates (2023)
* The Truth vs. Alex Jones (2024)

|

Literature|

* Give a Boy a Gun (2000)
* Nobody Left to Hate (2001)
* No Easy Answers (2002)
* After (2003)
* Columbine (2009)
* Hate List (2009)
* "'No Way to Prevent This,' Says Only Nation Where This Regularly Happens" (2014–)
* A Mother's Reckoning (2016)

Other|

* Bang Bang You're Dead (1999)
* Pico's School (1999)
* Lullaby for Columbine (1999)
* "Shoot" (1999/2010)
* "The Nobodies" (2000)
* Columbinus (2005)
* Super Columbine Massacre RPG! (2005)
* V-Tech Rampage (2007)
* "Valentine's Day" (2013)
* The Library (2014)

Related terms
and topics|

* Active shooter
* Columbine effect
* Gun violence in the United States
* List of school shootings in the United States by death toll
* Mass shootings in the United States
* Thoughts and prayers
* School shooting
* School violence

* v
* t
* e

Firearms (list, glossary, and topics)

* Firearm
* lists
* Gun
* History
* Safety
* War
* Weapon

Types of firearms

* Breechloader versus muzzleloader
* Combination weapons
* Combination
* Elephant
* Flare gun
* Line thrower
* Long gun
* Carbine
* Musket
* Takedown
* Multiple-barrel (list)
* Needler
* Net gun
* Pen gun
* Riot gun
* Rotary
* Single-shot
* Sleeve gun
* Smoothbore
* Spring-gun
* Underwater firearm

Handguns|

* Cane gun
* Derringer
* Duelling
* Pistol
* list
* Machine
* Pepper-box
* Pocket
* Revolver
* list
* Semi-automatic pistol
* list
* Pistol caliber
* Personal defence weapon
* Submachine gun
* Starting
* Wallet gun

Rifles (list)|

* Anti-materiel
* Anti-tank
* Assault
* list
* Automatic
* Battle
* list
* Carbine
* list
* Double
* Hunting
* Buffalo
* Elephant
* Express
* Punt
* Varmint
* Marksman
* Rifling
* Polygonal
* Repeating
* Sniper
* list

Machine guns|

* General purpose
* Light
* Medium
* Heavy
* SAW

Shotguns (list)|

* Automatic shotgun
* Coach gun
* Combat shotgun
* Double-barreled
* Pump action
* Riot
* Sawed-off
* Boomstick

Ammunition|

* 20-gauge shotgun
* Breaching round
* Dragon's breath
* Shotgun shell
* .410 bore
* Shot
* Slug

Historic or famous|

* AK-47
* AR-15
* M16
* M4
* Antique firearms
* Barrett M82
* Gatling gun
* Winchester rifle
* Browning machine gun
* M1 Garand
* Mauser rifles
* TEC-9
* Tommy Gun
* MP 40
* MAC-10
* Uzi
* Colt Peacemaker
* Calico
* M1911
* Glock

Mechanics and components

Components|

* Barrel
* Feed ramp
* Slug
* Threads
* Trunnion
* Bayonet
* Belt
* Blank-firing adapter
* Breechblock
* Breechface
* Bolt
* Rotating
* Telescoping
* Flapper
* Roller
* Tilting
* Bump stock
* Chamber
* Cocking handle
* Cylinder
* Extractor
* Firing pin
* Flash suppressor
* Fluting
* Forward assist
* Freebore
* Forearm
* Foregrip
* Hammer
* Half-cock
* Linear
* Striker
* Lock
* Flintlock
* Wheellock
* Magazine
* Bottom metal
* Clip
* Drum
* High-capacity
* Speedloader
* Stripper clip
* Muzzle brake
* Muzzle shroud
* Pistol grip
* Pistol slide
* Rail system
* Receiver
* Recoil pad
* Rim
* Safety
* Sear
* Auto sear
* Shroud
* Silencer
* Squeeze bore
* Choke
* Stock
* Synchronization gear
* Tapering
* Trigger
* guard

Sights|

* Diopter
* Finderscope
* Globe
* Holographic
* Iron
* Laser
* Reticle
* Reflex
* Red dot
* Magnifier
* Scope mount
* Tang
* Telescopic
* Night vision
* Thermal
* Zeroing

Actions|

* Blowback
* Blow-forward
* Bolt
* Boxlock
* Breechloading
* Break
* Open bolt
* Closed bolt
* Electronic
* Gas-operated
* Lever
* Muzzleloading
* Out-of-battery
* Pump
* Push/Controlled feed
* Recoil-operated
* Repeating
* Revolver
* Self-loading
* Single-shot
* Slamfire

Physics|

* Ballistics
* Ballistic coefficient
* External
* Terminal
* Transitional
* Physics of firearms
* Rangefinding/keeping
* Mathematics
* Stadiametric

Metrics|

* Accurizing
* Bore axis
* Caliber
* Circular error probable
* Effective range
* Gauge
* Gun chronograph
* Gun harmonisation
* Headspace
* Length of pull
* Lock time
* Match grade
* Mean time between failures
* Minute of Angle (MOA)
* Muzzle
* Energy
* Rise
* Velocity
* Penetration
* Power factor
* Precision-guided
* Rate of fire
* Recoil
* Group
* Stock measurements
* Stopping power
* Handgun effectiveness
* Twist rate

Shooting and ammunition

Gunshot|

* Dry fire
* Firing (Shooting)
* Gunshot
* Firefight
* Maintenance
* Field strip
* Fouling
* Malfunction
* Cooking off
* Hang fire
* Squib load
* Ricochet

Ignition|

* Fire forming
* Obturation
* Primer
* Gunpowder
* Percussion cap
* Rimfire
* Tubes and Primers
* Propellant
* Ball propellant
* Cordite
* Improved Military Rifle
* Ramrod
* Smokeless powder

Ammunition|

* Cannelure
* Dummy round
* Snap cap
* Flechette
* Gas check
* Overpressure ammunition
* PCA
* Sabot
* Wadding

Bullets|

* Armour piercing
* Cast
* Expanding
* Full metal jacket
* Frangible
* Green
* Incendiary
* High explosive
* HEIAP
* Projectile
* Raufoss
* Round shot
* SLAP
* Soft point
* Supercavitating
* Total metal jacket
* Tracer
* Hollow base
* Hollow point
* Minié
* Meplat
* Plastic tipped
* ABCBC
* Snake shot
* Spitzer
* VLD

Cartridges|

* Blank
* Caseless
* Centrefire
* Handloading
* Rifle cartridge
* Fully powered
* Intermediate
* list
* Paper
* Pinfire
* Wildcat

Society, safety, industry, and laws

Society|

* Celebratory gunfire
* Civilian gun ownership
* Household ownership rates
* Exhibition shooting
* Gun cultures
* United States
* Gun shows
* State firearms
* Hunting
* Jungle style
* Pistol duelling
* Politics
* Shooting sports
* Civilian Marksmanship Program

Gun violence
and safety|

* in the United States
* Assassinations
* Deaths
* Forensics
* Gunfighter
* Gun safety

Firearm industry|

* 3D printed firearm
* list
* Firearm brands
* Firearms by country
* Gun shops
* list
* Gunsmith
* Improvised firearm
* Most-produced
* Privately made
* Small arms trade

Arms control|

* Arms and Gun control
* Disarmament
* Campaign Against Arms Trade
* Featureless rifles

Gun laws|

* Air travel
* Assault weapons
* Concealed carry
* in the U.S.
* License
* High-capacity magazine ban
* Right to bear arms
* Small Arms & Light Weapons (SALW)

United States Gun|

* Laws (by U.S. state)
* Legislation
* Politics
* Federal Assault Weapons Ban

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