Sexually Frustrated Mass Shooters: A Study of Perpetrators,Profiles,Behaviors,and Victims

Abstract

Although several mass killings by incels have received much attention, the overall phenomenon of sexually frustrated offenders seems even larger. This study drew from a recently developed sexual frustration theory to closely examine public mass shooters in the United States from 1966 to 2021 (n = 178). Results showed that some sexually frustrated perpetrators just wanted sex, while others lusted after unavailable partners or had illegal urges that were difficult to satisfy. Quantitative analyses indicated that compared to other mass shooters, sexually frustrated perpetrators were more frequently young, male, unmarried, childless, and unemployed. They were also more likely to be misogynistic, sex offenders, and fame-seekers, and their attacks killed significantly more female victims. Concerted efforts to reduce toxic masculinity and provide better guidance to young men could help reduce this threat.

Keywords

incels mass shootings sexual frustration theory misogyny sex offending

Introduction

The relationship between sexual frustration and violence has been discussed for centuries (Kanin, 1967; Karras, 1998; Weeks, 1985), but recent concerns have focused on mass killings by involuntarily celibate men (i.e., “incels”). The 2014 Isla Vista shooter is often cited as the first case of this type (Hoffman et al., 2020).¹ He wrote a manifesto about his sexual frustration, warned “I don’t know why you girls aren’t attracted to me, but I will punish you all for it,” and then killed his roommates and attacked a sorority house (Cottee, 2021, p. 106). A year later, the 2015 Umpqua Community College shooter praised the Isla Vista shooter, complained about being a virgin, and lamented “I long ago realized that society likes to deny people like me. . .it’s not fair” (Langman, 2021a). More recently, the 2018 Tallahassee shooter—who identified with incels, complained about the male “virginity burden,” and had a history of sexual misconduct—shot six women in a hot yoga class (Barrouquere, 2018).²

In researchers’ efforts to understand this growing threat, many have studied incel communities, perspectives, and “ideologies.” Some estimate that as many as 100,000 people participate in incel forums online (Anti-Defamation League, 2020). And while the vast majority of incels do not commit mass murder and some do not support violence (Daly & Reed, 2022; Pantucci & Ong, 2020; Speckhard et al., 2021; Voroshilova & Pesterev, 2021), many participants in incel forums may contribute to a social climate in which mass killings and attacks against women become increasingly likely (Caruso et al., 2021; Cottee, 2021; Hoffman et al., 2020; O’Malley et al., 2020; Scaptura & Boyle, 2020; Speckhard et al., 2021). The most problematic incel perspectives blame women for men’s sexual frustration and contain themes of misogyny, victimhood, and fatalism (Cottee, 2021; Ging, 2019; Jaki et al., 2019; O’Malley et al., 2020; Tranchese & Sugiura, 2021; Voroshilova & Pesterev, 2021).

However, mass shooters who considered themselves “incels” represent only a fraction of the overall phenomenon. Most sexually frustrated mass killers—including the 2014 Isla Vista shooter—were not participants in incel communities or well versed in incel terminology. And sexually frustrated mass shooters are nothing new. Perpetrators who struggled with similar issues and responded with anger, misogyny, and violence existed long before the Isla Vista attack—and even before the internet. Given the recent interest in sexually frustrated mass shooters, it is worth looking more comprehensively at this subject to see what else can be learned.

This study will closely examine sexual frustration problems among public mass shooters who attacked in the United States from 1966 to 2021 (n = 178). It draws from a recently developed sexual frustration theory of aggression, violence, and crime (Lankford, 2021) to explore four main questions. First, how common are sexual frustration problems among mass shooters? Second, do sexually frustrated mass shooters have a different profile than other mass shooters? Third, do sexually frustrated mass shooters behave differently than other mass shooters? And fourth, is there a difference in which victims sexually frustrated mass shooters choose to kill? No one commits mass murder due to sexual frustration alone, but it seems like an understudied factor, given its primacy in the complaints of some recent attackers.

Sexual Frustration Theory

In general, a large body of literature has shown that when people experience significant frustrations or strains, they are more likely to act aggressively or commit crimes (Agnew, 1992; Berkowitz, 1989; Breuer & Elson, 2017; Brezina, 2017). These problems can include financial difficulties, struggles at work or school, negative social relationships, the loss of friends or family, and more (Agnew, 1992; Brezina, 2017). It seems clear that many people with these same experiences do not commit serious crimes. However, if the frustration or strain felt unexpected, unjust, like someone else’s fault, or harmful to one’s self-efficacy, people are more likely to respond in antisocial ways (Agnew, 1992; Berkowitz, 1989; Breuer & Elson, 2017; Brezina, 2017).

Sexual frustration may also increase the risks of aggression, violence, and crime (Lankford, 2021). The clearest form of sexual frustration exists among people who are “involuntarily celibate,” which in its original meaning referred to anyone who wanted sex but could not have it (Donnelly et al., 2001). This includes people who are virgins, single and unable to find a partner, or in a sexless relationship (Donnelly et al., 2001). In a recently developed theory, Lankford (2021) took this a step further and suggested that almost everyone may experience sexual frustration on occasion—regardless of their gender, orientation, relationship status, or sexual history. However, these frustrations vary in frequency and severity, and they become the biggest source of dissatisfaction in some individuals’ lives (Daly & Reed, 2022; Lankford, 2021). Although the determinants of sexual frustration are complex, the most significant problems may be experienced by people who have the most powerful sex drives, who are most frequently exposed to arousing stimuli, who have the largest discrepancy between their sexual expectations or fantasies and their sexual behavior, and who are most prone to obsess or fixate on their desires (Lankford, 2021). If incels represent one extreme, some people with compulsive or hypersexual desires may represent the other. Despite having sex often, they may frequently be frustrated, much like other people with addictions who are commonly unsatisfied despite often experiencing their activity or drug of choice (Lankford, 2021).

Lankford (2021) suggests there are three major types of sexual frustration associated with (1) unfulfilled desires to have sex, (2) unavailable partners, and (3) unsatisfying sexual activities. This is also described as the “inability to have sex when one wants, with whom one wants, how one wants” (Lankford, 2021, p. 4). For instance, people can become frustrated because they want sex soon but have to wait, because they desire sex with a specific person or type of person who is unavailable to them, or because the type of sexual activity they can engage in feels physically or psychologically unsatisfying. People who are content in one area may be frustrated in another. For example, someone who frequently masturbates could be upset about being unable to engage in other sex acts, and someone who can only have sex with one partner could be aggravated about not being able to have sex with others (Lankford, 2021).

Sexual frustration can be profoundly shaped by social norms and gendered expectations (Ging, 2019; Glace et al., 2021; Scaptura & Boyle, 2020; Tranchese & Sugiura, 2021). In the United States, girls have traditionally been socialized to view virginity as a “gift” for their first partner, and sex as something that should be saved for a loving and committed relationship (Carpenter, 2002). For girls and women, waiting to have sex is thus often framed as a virtue—although these norms may be changing (Carpenter, 2002). By contrast, boys often learn that their virginity is a source of stigma and an easy target for insults, which can then increase the pressure they feel to have sex as soon as possible (Carpenter, 2002; Fleming & Davis, 2018). Beyond virginity loss, hegemonic and toxic masculine norms have led some men and boys to believe that they are entitled to women’s submission, that women are sexual objects to be “used” for their pleasure, that by degrading women they can increase their power and status, and that by having a large number of sexual “conquests” they can prove their worth as a man (Manne, 2018, 2020; Scaptura, & Boyle, 2020; Tranchese & Sugiura, 2021). Men and boys who have embraced these views may be especially prone to consider their sexual frustration unexpected, unjust, someone else’s fault, or harmful to their self-efficacy, which the aforementioned research on frustration and strain suggests would increase risks of antisocial behavior (Agnew, 1992; Berkowitz, 1989; Breuer & Elson, 2017; Brezina, 2017).

Overall, certain types of people seem more likely to have sexual frustration problems than others. For instance, men may be especially susceptible, given the aforementioned influence of gender norms and evidence that on average, they report wanting sex more frequently than women, exhibit more desire for casual sex with strangers, and appear more likely to masturbate, use pornography, or solicit sex workers (Hooven, 2021; Lippa, 2009). Unmarried people may tend to be more sexually frustrated as well. The unmarried group includes both extremes: people who have gone a long time (such as a year or more) without sex (Ueda et al., 2020), and people who are hypersexual, constantly seeking new partners, and rarely satisfied (Lankford, 2021). In addition, people without children may be more sexually frustrated than parents, on average, because they do not have to invest time and energy in raising kids and tend to focus more on sexual partners (Dawkins, 1976; Hooven, 2021; Walsh & Jorgensen, 2018). Although the evidence is less clear, young people may typically be more sexually frustrated as well, given the relationship between growing up, increased hormones, and sexual discovery (Hooven, 2021; Wu et al., 2016). In turn, unemployed people may tend to experience more sexual frustration than those with jobs, given the relationship between lower social status and reduced sexual opportunities—especially for men (Kanazawa, 2009).

Sexual frustration may be associated with at least four types of behavioral consequences: (1) relief-seeking, (2) power-seeking, (3) revenge-seeking, and (4) displaced frustration (Lankford, 2021). These behaviors do not always involve aggression, violence, or crime, but they certainly can. For example, sexually frustrated individuals may be more likely to (1) commit crimes that bring them temporary relief, such as soliciting sex workers or engaging in sex offending; (2) seek greater sexual power through crimes that will increase their fame, social status, wealth, or control over other people; (3) punish whomever they blame for their sexual struggles; or (4) lash out at those around them. Men and boys who subscribe to traditional gender norms seem especially likely to respond to masculinity challenges with unhealthy overcompensations (Messerschmidt, 2000; Willer et al., 2013), so if they interpret their sexual frustration as an indictment of their masculinity, the risks of violence may increase significantly.³

Public Mass Shooters and Sexual Frustration

The profile of public mass shooters appears remarkably similar to the aforementioned profile of those who seem most likely to experience sexual frustration problems. Most notably, public mass shooters are almost always male (Duwe, 2020). They also tend to be young (Lankford et al., 2021). In addition, approximately 80% of perpetrators are unmarried when they attack, and they appear unlikely to have children (Peterson & Densley, 2021). Finally, public mass shooters are more likely to be unemployed than the average American (Lankford et al., 2021). Overall, this suggests that being young, male, unmarried, childless, and unemployed may be associated with both sexual frustration problems and public mass shootings.

Prior research has also found that public mass shooters often experience a wide range of frustrations and strains before they attack (Langman, 2021b; Lankford & Silva, 2021; Levin & Madfis, 2009; Newman et al., 2004; Peterson & Densley, 2021; Silver et al., 2018). These can include social marginalization; conflicts with peers, family members, or romantic partners; problems at work or school; and more (Fox & Levin, 1994; Langman, 2021b; Lankford & Silva, 2021; Levin & Madfis, 2009; Peterson & Densley, 2021; Silver et al., 2018; Vossekuil et al., 2004). In addition, many perpetrators struggle with mental health problems (Duwe, 2020; Peterson & Densley, 2021; Silver, et al., 2018; Vossekuil et al., 2004), although some have not been directly assessed and therefore lack a formal diagnosis (Lankford & Cowan, 2020). Because public mass shooters often lived with mental illness for years before attacking, it is clearly not the sole explanation for their behavior, but just one piece of the overall puzzle (Lankford & Silva, 2021).

Each of these factors may exacerbate sexual frustration or be exacerbated by it. For instance, Check et al. (1985) found that lonely men are especially likely to consider sexual relationships between men and women adversarial, to be sensitive to date rejection, and to support violence against women. These toxic attitudes may then lead them to become even more lonely and hostile (Check et al., 1985). More broadly, when people are socially disconnected, in conflict, having problems at work or school, and/or struggling with mental health problems, that may make it more difficult for them to find or maintain a healthy relationship (Check et al., 1985; Donnelly et al., 2001; Van Brunt & Taylor, 2020). And conversely, if severe sexual frustration is associated with aggression, jealousy, irritability, reduced empathy, and depleted self-control—as sexual frustration theory suggests (Lankford, 2021)—sexually frustrated individuals may perform worse at work or school, have more inappropriate and alienating social interactions, and feel deeply depressed about their sexual failures. All of this could influence their eventual decision to attack.

However, the prevalence of sexual frustration problems among mass shooters remains unknown. There have been some great qualitative studies of incel mass killers that looked closely at a single case or a few cases, and analyzed them in depth (Allely & Faccini, 2017; Collins & Clark, 2021; Hoffman et al., 2020; Manne, 2018, 2020; O’Donnell, 2021; Witt, 2020). Other research has identified some successful and thwarted attackers who had misogynistic views, committed violence against women, or were sexually frustrated—including some incels (Van Brunt & Taylor, 2020). There has also been one comprehensive study of gender-based mass shootings, which found that approximately one-third of U.S. incidents were influenced by the perpetrator’s anger against a specific woman or women in general (Silva et al., 2021). But our review of the literature could not find any dedicated attempts to estimate the overall proportion of mass shooters with sexual frustration problems. The only relevant finding comes from the Federal Bureau of Investigation’s 2018 active shooter report (Silver et al., 2018), which found sexual stress/frustration among 13% (8 of 63) active shooters in the United States from 2000 to 2013.⁴ This is likely a significant underestimate because the FBI’s researchers focused on information “memorialized, shared, or otherwise noted in some way (e.g., in the active shooter’s own writings, in conversation with family or friends, work files, court records)” (Silver et al., 2018, p. 16). Perpetrators who did not speak or write about their sexual struggles might not be counted, even if their behavior—like soliciting a sex worker—suggests they qualified.

The Present Study

Research Questions and Hypotheses

As noted earlier, this study explored four main research questions. First, how common are sexual frustration problems among public mass shooters? Second, do sexually frustrated mass shooters have a different profile than other mass shooters? Third, do sexually frustrated mass shooters behave differently than other mass shooters? And fourth, is there a difference in which victims sexually frustrated mass shooters choose to kill?

We hypothesized that sexual frustration problems would be found among a significant subset of public mass shooters, not only the handful of cases identified in past research. Consistent with sexual frustration theory (Lankford, 2021), we expected to find mass shooters with a range of issues, including frustration arising from unfulfilled desires to have sex, unavailable partners, and unsatisfying sexual activities.

Our second hypothesis was that sexually frustrated mass shooters would have a different profile than other mass shooters. Sexual frustration theory suggests that males, unmarried people, and people without children are highly susceptible to these issues, and that sexual frustration may be an important cause of misogyny (Lankford, 2021). We similarly hypothesized that compared to other perpetrators, sexually frustrated mass shooters would more often be young, male, unmarried, childless, unemployed, and misogynistic.⁵

Our third hypothesis was that sexually frustrated mass shooters would behave differently than other mass shooters. Consistent with sexual frustration theory, we expected them to show more signs of relief-seeking, power-seeking, revenge-seeking, and displaced frustration (Lankford, 2021). This might show up in several ways. For instance, they may be more likely to have a history of sex offending, to seek the power that comes with fame and celebrity status, and to have committed domestic abuse or other physical violence in the past.

Our fourth hypothesis was that sexually frustrated mass shooters would kill more female victims than other mass shooters. This could be associated with their misogyny, power-seeking, and revenge-seeking, and would suggest that sexual frustration can influence who they decide to target.

Although this study was informed by sexual frustration theory (Lankford, 2021) and tested several of its key tenets, it cannot be considered a complete empirical test of the theory—for a few reasons. First, while identifying correlates of sexual frustration among mass shooters can yield important insights, these correlates should also be studied in samples that include the general population, and thus capture more variation in subjects’ aggressive and violent behaviors. Second, the theory suggests that sexual frustration can have a causal effect on aggression, violence, and crime, but this study was not designed to test causation. Even if the profiles and behaviors of sexually frustrated mass shooters are consistent with the theory, that will not confirm precisely how influential sexual frustration was on each perpetrator’s decision to attack.

Identifying Public Mass Shooters

We studied all public mass shooters who attacked in the United States from January 1966 to June 2021 (n = 178), according to The Violence Project’s database (version 4), which was funded by the National Institute of Justice and compiled by Peterson and Densley (2021). Public mass shooters are a subtype of mass murderer who attack with a firearm in a public location, such as a school, workplace, movie theater, mall, church, or restaurant (Duwe, 2020; Krouse & Richardson, 2015; Peterson & Densley, 2021). Other types of mass murderers, such as those who attack solely in private homes or who commit shootings due to “underlying criminal activity or commonplace circumstance (armed robbery, criminal competition, insurance fraud, argument, or romantic triangle),” are believed to be psychologically and behaviorally different and are typically analyzed separately (Krouse & Richardson, 2015, p. 10). In The Violence Project’s database, public mass shooters are defined as those who killed four or more victims (Peterson & Densley, 2021).⁶

Identifying Sexual Frustration Problems

Because most people experience sexual frustration on occasion, we attempted to identify public mass shooters whose struggles were sufficiently severe that they constituted a sexual frustration problem. As an analogy, many people drink alcohol, but if their behavior reaches a certain level of severity, it becomes a drinking problem. We coded perpetrators as having a sexual frustration problem if they (1) specifically complained about their sexual frustration or failure to find an intimate partner, (2) were believed by people who knew them (e.g., friends or family) or who closely studied their lives (e.g., other investigators or researchers) to have been sexually frustrated or frustrated with their failure to find an intimate partner, (3) solicited a sex worker, (4) stalked or harassed a desired partner in an attempt to establish or re-establish an intimate relationship, (5) exhibited interest in or engaged in sex with minors, (6) exhibited interest in or engaged in violent or illegal fetishes or paraphilias, or (7) engaged in other inappropriate or illegal sexual relief-seeking (e.g., was a “peeping tom” or masturbated in public).

Most of these criteria are obvious indicators that the individual had a sexual frustration problem, but several warrant additional comment. We included mass shooters who engaged in stalking or harassment to establish or re-establish an intimate relationship because these tactics have commonly been used by individuals attempting to obtain sexual opportunities or gain sexual power (Lankford, 2021). We included perpetrators who solicited a sex worker because this is illegal almost everywhere in the United States and suggests the individual’s frustration was so severe that he was willing to risk arrest. And we included perpetrators who exhibited interest in sex with minors or in violent or illegal fetishes or paraphilias because this suggests sexual desires the individual would not be able to regularly satisfy without significant personal risk (Briere & Runtz, 1989; Levenson et al., 2020). We did not consider sex offending to be prima facie evidence of sexual frustration problems because although some sex crimes may involve sexual frustration, many sex crimes are about both power and sex, and perpetrators could have other motives instead (Brownmiller, 1975; Stevens, 1995).⁷ We also did not count perpetrators as sexually frustrated merely because they were single, were recently broken up with, or had misogynistic views.

To determine which mass shooters met the qualifying criteria, we closely studied the lives of each individual based on all open-source information we could find from reliable sources, such as journal articles, previous scholarship, and books; government reports and official investigations; news reports; and suicide notes, manifestos, or online posts from the shooters’ themselves. The authors, who have experience compiling perpetrator information using similar methods and data sources, each participated in all parts of this process: studying the perpetrators’ lives, using the qualifying criteria to code them, and discussing the results to ensure consistency and accuracy. There were not any cases in which the authors disagreed after the coding and discussion stages were complete.

Additional Variables for Comparison

Data on public mass shooters’ profiles and behavior were drawn from The Violence Project’s database (Peterson & Densley, 2021). For profiles, we examined perpetrators’ sex, age, relationship status, parental status, and employment status, along with whether they had recently experienced a romantic breakup or were known to have a misogynistic prejudice.⁸ For their pre-attack behavior, we considered whether perpetrators had histories of sex offending, physical violence, and domestic abuse. Regarding their attacks, we analyzed whether shooters’ motives involved fame-seeking or a relationship issue, where they attacked, and whether their attacks ended in them committing suicide, being shot and killed, or being arrested. We supplemented The Violence Project’s data on perpetrators’ fame-seeking motives with publicly available findings from other research (Lankford, 2016; Silva & Greene-Colizzi, 2019b).⁹ We also studied the total number of victims killed by each mass shooter and how many of those victims were male and female.¹⁰ Victims’ sex was analyzed in several ways: (1) the average number of male and female victims that mass shooters killed, (2) the percentage of all victims they killed who were male or female, (3) whether they killed four or more male or four or more female victims, and (4) whether they killed only male or female victims. We also considered whether perpetrators killed or injured their intimate partner during (or shortly preceding) their attack. For the four cases in the dataset that involved two mass shooters attacking together, both were considered responsible for all victims killed. Continuous variables were coded as numbers and binary variables were coded as 1 = yes and 0 = no/no evidence. Additional information on the variables used to compare mass shooters can be obtained directly from The Violence Project (Peterson & Densley, 2021), which provided the dataset for this study.

Quantitative Analysis

Fisher exact tests, chi-square tests (χ²), and t-test analyses were conducted to determine whether the average differences between mass shooters with and without sexual frustration problems are statistically significant. We used Fisher’s exact tests because they are appropriate for both small and large sample sizes. However, to make sure our results were not a product of that decision, we also ran Pearson’s chi-square tests for all variables in which cell sizes were large enough, and there was no change in levels of significance (p < .05, .01, and .001). To further test the sensitivity of findings, the t-tests examining the victims killed, male fatalities, and female fatalities were conducted with and without the two cases with the highest victim counts (the 2016 Orlando Pulse shooting and 2017 Las Vegas shooting). There was no change in levels of significance (p < .05, .01, and .001) due to these outliers.

Results

Although it appears no prior study found sexual stress or frustration among more than 13% of shooters (Silver et al., 2018), we found that approximately one-third of public mass shooters in the United States had sexual frustration problems.¹¹ Remarkably, this included many of the deadliest mass shooters in American history, even though they have not been previously analyzed through this lens. As examples:

The 1986 Edmond post office shooter (who inspired the phrase “going postal”) was known as a “peeping tom” in his neighborhood, rubbed up against women in his office, and was fired after he cornered a woman in the elevator and “wouldn’t let her out” (Robbins, 1986; Murderpedia, n.d.).

The 1991 Luby’s cafeteria shooter (who committed the deadliest U.S. shooting at that time) sent a letter to two sisters he said he had been attracted to since they were 15 and 17. He complained he lacked “information that would help me lead to your capture,” requested they send him “nice pictures,” and asked, “Do you think the three of us can get together some day?” (United Press International, 1991).

The 1999 Columbine shooter (E.H.) wrote “Maybe I just need to get laid. Maybe that’ll just change some shit around. . .I want to grab a few different girls in my gym class, take them into a room, pull their pants off and fuck them hard. . .ahhh I just want to fuck! Call it teenager hormones or call it a crazy fuckin racist rapist” (Langman, 2014b).

The 2007 Virginia Tech shooter hired a woman from an escort service a month before his rampage, but she reportedly rejected his attempt to have sex with her (Langman, 2018). He also stalked women at his university who would not date him, and the first line of his manifesto complains about “the happiness I could have had mingling among you hedonists” (Langman, 2014a).

The 2012 Sandy Hook shooter “had an interest in children that could be categorized as pedophilia,” according to a behavioral analysis unit (Collins, 2017). In an online post, the shooter commented that a frustrated penis that is looking for a sexual partner and gets repeatedly rejected “would get a gun and go on a rampage. No seriously” (Langman, 2015).

The 2016 Orlando Pulse nightclub shooter had a “secret sex life that included using escorts and dating services such as Plenty of Fish, and asking a friend to cover for him—all to cheat on his wife.” He had a yearlong affair with one woman that ended three months before his attack, and he propositioned other women for sex (Hayes, 2017).

The 2017 Las Vegas shooter had a girlfriend he was no longer having sex with, but he also had “several hundred images of child pornography” on his computer, according to the official post-investigation report (Las Vegas Metropolitan Police Department, 2018).

The 2018 Parkland shooter had recently searched online for Asian mail-order brides, “little teen pirn (porn),” “how to get into a relationship,” “how to get a girlfriend,” and “how not to be afraid of the girl you like.” Shortly before his attack, he praised the Isla Vista shooter online, and his last text messages were to the ex-girlfriend who dumped him (Public Safety Commission, 2019).

Table 1 presents the results from our quantitative comparisons between the profiles of mass shooters with and without sexual frustration problems. There were many statistically significant differences. Sexually frustrated perpetrators were significantly more likely to be young, unmarried, single, childless, and misogynistic. Although higher proportions of sexually frustrated perpetrators were also male and unemployed, these differences were not significant at the p < .05 level. The percentage of perpetrators with a recent breakup was essentially the same across groups.

Table 1.

Comparing Profiles of Mass Shooters With and Without Sexual Frustration Problems.

	Sexually frustrated mass shooters (n = 56)		Other mass shooters (n = 122)
	N	%/M	n	%/M	χ²/t-test
Sex (male)	56	100%	118	97%	1.878
Age	—	30.8	—	35.4	2.350	*
Under 25 years old	24	43%	26	21%	8.821	**
Unemployed	39	70%	71	58%	2.130
Single	44	79%	74	61%	5.513	*
Unmarried	51	91%	95	78%	4.537	*
Childless	49	88%	77	63%	11.037	***
Recent breakup	12	21%	26	21%	0.000
Misogynistic	18	32%	4	3%	29.522	***

p < .05. **p < .01. ***p < .001.

As shown in Table 2, sexually frustrated mass shooters also differed from other mass shooters according to their behavior. For instance, they were over six times more likely to have a history of sex offending, and approximately 50% more likely to have a history of domestic abuse. They sought fame much more often as well. Perpetrators with sexual frustration problems were also more likely to attack at school and less likely to attack outdoors. No significant differences were found regarding their histories of physical violence, their being motivated by a relationship issue, their other attack locations, or the outcomes of their attacks (i.e., committing suicide, being shot and killed, or being arrested).

Table 2.

Comparing Behaviors of Mass Shooters With and Without Sexual Frustration Problems.

	Sexually frustrated mass shooters(n = 56)		Other mass shooters(n = 122)
	n	%	n	%	χ²
Pre-attack behavior
History of sexual offenses	22	39	7	6	31.675***
History of physical violence	38	68	75	62	0.674
History of domestic abuse	26	46	38	31	3.892*
Attack behavior
Fame-seeking motive	22	39	7	6	31.675***
Relationship issue motive	7	13	19	16	0.291
Incident location
School	16	29	7	6	17.785***
Government	0	0	6	5	2.850
House of worship	5	9	6	5	1.065
Retail	10	18	29	24	0.784
Restaurant	6	11	19	16	0.751
Workplace	14	25	42	34	1.582
Place of residence	9	16	23	19	0.201
Outdoors	3	5	29	24	8.825**
Perpetrator resolution
Suicide	27	48	42	34	3.074
Killed	7	13	28	23	2.654
Apprehended	22	39	52	43	0.176

Note. The location variables are not mutually exclusive because some attacks occurred in multiple locations (e.g., inside a building and outdoors).

p < .05. **p < .01. ***p < .001.

Findings on the number and sex of victims killed by mass shooters are presented in Table 3. Overall, sexually frustrated perpetrators killed more total victims, on average, than other perpetrators. And while both groups averaged more male victims killed than female victims, sexually frustrated mass shooters appeared much more interested in killing women or girls. This can be observed in several different ways. First, sexually frustrated mass shooters averaged significantly more female victims killed (M = 4.4) than other mass shooters (M = 2.3). Second, a higher percentage of the victims killed by sexually frustrated perpetrators were female (46%) than for other mass shooters (36%). Third, sexually frustrated mass shooters were significantly more likely to kill four or more female victims (50% did this) than other mass shooters (19% did this). And fourth, although killing only female victims was rare for both groups, sexually frustrated perpetrators were significantly more likely to do this (9%) than other perpetrators (3%).

Table 3.

Comparing Victims Killed by Mass Shooters With and Without Sexual Frustration Problems.

	Sexually frustrated mass shooters (n = 56)		Other mass shooters (n = 122)
	n	%/M	n	%/M	χ²/t-test
Number of victims killed	—	9.6	—	6.1	−2.519	**
Male victims
Number of male victims killed	—	5.2	—	3.8	−1.650
Percentage of victims killed who were male	—	54%	—	64%	2.260	*
Shooter killed ≥4 male victims	28	50%	53	43%	0.666
Shooter killed only male victims	5	9%	23	19%	2.852
Female victims
Number of female victims killed	—	4.4	—	2.3	−2.647	**
Percentage of victims killed who were female	—	46%	—	36%	−2.274	*
Shooter killed ≥4 female victims	28	50%	23	19%	18.216	***
Shooter killed only female victims	5	9%	3	3%	3.743	*
Shooter killed or injured intimate partner	4	7%	17	14%	1.701

Note. Data on whether the shooter killed or injured an intimate partner only includes violence during (or shortly preceding) the mass shooting incident. In the four cases that involved two shooters attacking together, both were considered responsible for all victims killed. There was no change in levels of significance due to the highest fatality outliers (the 2016 Orlando Pulse shooting and 2017 Las Vegas shooting). For the percentage of victims killed (by each shooter) who were male or female, each individual perpetrator had a value between 0 and 100, so t-tests were used to identify significant differences across groups.

p < .05. **p < .01. ***p < .001.

Notable examples of shooters who admitted being sexually frustrated and disproportionately killed female victims include the 2006 Amish school shooter and the 2021 Atlanta Spa shooter. In the former case, the perpetrator told his wife that he had molested girls in the past and had been “daydreaming about molesting again” (Langman, 2018). He took underage girls hostage before killing five of them. In the Atlanta case, the perpetrator confessed after his arrest that he was a “sex addict” who carried out the shootings as a way to rid himself of his “temptations” (Jeltsen, 2021). He attacked massage parlors where sex workers offered erotic services, killing seven women and one man.

The other tests indicated minimal differences between the groups. When it came to male victims, the only statistically significant difference was that a lower percentage of victims killed by sexually frustrated perpetrators were male (54%) than for other mass shooters (64%). No significant difference was found in which group was more likely to kill or injure an intimate partner during (or shortly preceding) their attack.

Discussion

This study examined the frequency of sexual frustration problems among public mass shooters in the United States. It then tested whether sexually frustrated perpetrators differ from other mass shooters based on their profiles, behaviors, and victims. In the following discussion, we address implications for understanding sexual frustration and violence, for future research, and for violence prevention.

Implications for Understanding Sexual Frustration and Violence

Overall, many of this study’s results were consistent with sexual frustration theory (Lankford, 2021). As hypothesized, sexual frustration problems were found among a significant subset of public mass shooters, not only in the handful of cases identified in past research; there was evidence of all three major types of sexual frustration identified in the theory; and sexually frustrated perpetrators fit the expected profile, which means they were significantly different from other mass shooters. As expected, the behavior of sexually frustrated mass shooters also seemed consistent with the theory, which suggests sexual frustration often leads to (1) relief-seeking, (2) power-seeking, (3) revenge-seeking, and (4) displaced frustration. Sexually frustrated mass shooters were significantly more likely than other mass shooters to have a history of sex offending, which could indicate they were seeking sexual relief from their victims, as well as power over them. These perpetrators were also more likely to have a history of domestic abuse, which could show their tendencies to be controlling (power-seeking), to hurt whomever they blame for their sexual frustration (revenge-seeking), or to lash out at those around them (displaced frustration). In addition, sexually frustrated perpetrators were also far more likely than other perpetrators to be seeking fame, which is commonly believed to confer increased power, social status, and sexual opportunities.¹²

The finding that sexually frustrated mass shooters killed both more total victims and more female victims than other mass shooters may also fit sexual frustration theory’s core tenets. For instance, all individuals in our sample were mass killers, but those who committed the deadliest attacks, on average, were those with sexual frustration problems. Perhaps this also indicates they were more motivated to seek the power of life-and-death over their victims, to seek revenge against those they blamed for their suffering, and to lash out in displaced frustration against random bystanders. Similarly, their more frequent killing of women and girls supported our hypothesis and may demonstrate the extent to which sexual frustration, toxic masculinity, and misogyny shaped their attacks.¹³

Although many of this study’s results fit what we expected based on sexual frustration theory, a few did not. For instance, sexually frustrated mass shooters were not significantly more likely to have a history of physical violence than other perpetrators. However, this was because more than 60% of individuals in both groups had a history of violence. If sexually frustrated perpetrators were compared to the much more peaceful general population, there would almost certainly be a significant difference in their violent pasts, as the theory suggests. Another unexpected finding was that sexually frustrated mass shooters were not significantly more likely than other perpetrators to have experienced a recent breakup, to be motivated by a relationship issue, or to have killed or injured their intimate partner during (or shortly preceding) their attack. This could be explained by the difference between sexual frustration and other gender-based resentments unrelated to sex (Silva et al., 2021). In other words, mass shooters without sexual frustration problems can also be influenced by toxic masculinity, and they may have been just as likely to respond to recent breakups or relationship issues with rage and violence against women. However, these results could also be explained by the shortcomings of these variables, which did not account for all forms of romantic rejection. For instance, the 2018 Santa Fe shooter had been rejected by a girl at his school for months, and a week before his attack, she stood up in class and said she would not date him (CBS, 2018). He eventually killed her during his attack. However, despite involving romantic rejection, this would not be considered a recent breakup, a relationship issue, or the murder of an intimate partner, because the two of them never dated.

Implications for Future Research

There are many important ways this subject could be explored in future research. For instance, scholars could use other forms of quantitative analysis to test for differences between sexually frustrated mass shooters and other perpetrators, such as multivariate regression models that can help identify interaction effects. They could also incorporate new variables, such as specific measures of romantic rejection.

As noted earlier, it would also be valuable to study correlates of sexual frustration among larger samples that include more variation in subjects’ aggressive and violent behaviors. Committing extreme violence was a constant among the members of our sample, not a variable. Even greater differences associated with sexual frustration might be identified if comparisons were made with law-abiding citizens, the general population, or people who committed less serious crimes.

Researchers could also generate new insights by studying sexually frustrated perpetrators in more depth. For instance, by examining the timing of events and behaviors in mass shooters’ lives, they could identify which factors seem most closely connected to the decision to attack (Lankford & Silva, 2021). As an example, we know that the 2018 Parkland shooter’s mother died, he was expelled from school, and he was dumped by his girlfriend (Public Safety Commission, 2019). But in the weeks preceding his attack, his internet searches and text messages revealed his desperation for an intimate partner—not a desire to find a surrogate mother or be reinstated at school (Public Safety Commission, 2019). This suggests that compared to these other factors, his sexual frustration may have had a larger influence on his desire to kill.

In other cases, however, sexual frustration and other life frustrations may interact. For instance, some mass shooters got in trouble at work or school because of their inappropriate sexual behavior. There were also some perpetrators who may have been particularly upset about being disciplined, fired, or expelled because they considered that a threat to their masculinity and a blow to their status, which could make it less likely that a potential partner would find them attractive. As noted earlier, sexual frustration can exacerbate other life problems, but the reverse is possible as well. It would be helpful to know more about the most common pathways to aggression, violence, and crime.

Finally, more research on the strategies people can use to reduce their sexual frustration would be of great value. Any sexual experience (including masturbation or soliciting a sex worker) could temporarily reduce sexual frustration if it helps satisfy the individual’s desires. However, temporary relief is unlikely to solve more extensive sexual frustration problems, much like illegal drug use or high-stakes gambling are unlikely to solve substance abuse or gambling problems. To this point, Lankford (2021) cites evidence that people with higher rates of masturbation actually report more dissatisfaction with their sex lives. Along similar lines, while it could be argued that the proliferation of online pornography should help reduce sexual frustration—because it gives users instant access to sexual sights and sexual sounds, whenever they like—it seems to have made toxic masculinity worse (Tranchese & Sugiura, 2021). As virtual reality technology continues to improve and immersive sexual substitutes become more common, it will be important to know whether they are part of the solution, or part of the problem.

Implications for Violence Prevention

This study’s findings have multiple implications for mass shooting prevention. Although no one commits mass murder due to a single factor, sometimes one change in someone’s life could prevent their attack. For some mass shooters, less access to weapons, more access to mental health treatment, or more support from family or friends could have made an important difference (Greene-Colozzi & Silva, 2020; Langman, 2021b; Lankford & Silva, 2021; Newman et al., 2004; Van Brunt & Taylor, 2020).

It is also possible that some mass shooters would not have attacked if not for their sexual frustration. As noted earlier, multiple perpetrators explicitly cited sexual frustration as one of their primary motives, so if that motive was removed, they may have lacked the desire to kill. Additionally, some mass shooters suggested that if they found sexual satisfaction, it may have altered their behavior. For instance, one of the 1999 Columbine shooters wrote “Possible girlfriends are coming then [redacted] I’ll give the phony shit up in a second,” and the other Columbine shooter suggested “Maybe I just need to get laid. Maybe that’ll just change some shit around” (Langman, 2014b, 2019). Similarly, the 2009 LA Fitness shooter wrote that if a woman he desired would be his girlfriend, he would “cancel this plan or put [it] on hold, at least for a while” (Goldman et al., 2009).¹⁴

It is important to emphasize, however, that being less frustrated does not necessarily require having more sex. Although some mass shooters might wish we could return to the “free love” and “make love, not war” culture of the American 1960s, another way to reduce frustration may be to recalibrate expectations. If society could make significant progress in scaling back toxic masculinity and other factors that lead certain men to believe they are entitled to women’s bodies, a more reasonable set of social expectations could take hold.

To this end, while sexual education (i.e., “sex ed”) is provided in most American schools, it often focuses on the biological aspects of sex and on avoiding unwanted pregnancies or sexually transmitted infections. Perhaps the curriculum should also educate young people (and especially young men) about sexual frustration. For example, it may help them to know that despite the impressions they may get from pop culture and social media, if they are not sexually active, that is entirely normal. Data on sexual activity in the United States suggest that approximately 7 million people aged 18 to 24 and 10 million people aged 25 to 44 did not have sex in the past year (Ueda et al., 2020).¹⁵ If young men are eager for sex but waiting for a willing partner, that is a common experience. It is not women’s fault or their own fault—and they are not alone.

In the meantime, one way to cope with sexual frustration may be to stay busy and distracted. When people obsess over what they want but cannot have—like the 1986 Edmond shooter, who would spend time in the office staring at women he worked with and desired—that seems to make things worse. And today, the risks of sexual obsessions may be even greater, given that frustrated individuals can spend hours at home “cyberstalking” the social media profiles of coworkers, fellow students, or other people they find attractive. However, when the U.S. military attempted to reduce its members’ solicitation of sex workers, their solution was not to focus on sex at all. Instead, they increased the educational, entertainment, and recreational opportunities available to everyone on site (Allred, 2006). If “idle hands are the devil’s playthings,” perhaps busy, distracted, and socially engaged people are less likely to fixate on their sexual frustration or to contemplate mass violence.

Limitations

We would like to acknowledge several research limitations. To begin with, this study relied on open-source data, which is limited by publicity and time-period effects (Silva & Greene-Colozzi, 2019a). This means that less may be known about incidents that received less media attention or were further in the past. However, open-source data has been found to reliably capture as much of the information that is found in official data sources, if not more (Huff-Corzine & Corzine, 2020; Parkin & Gruenewald, 2017). Furthermore, one benefit of using The Violence Project’s database (Peterson & Densley, 2021), which focuses exclusively on perpetrators who killed four or more victims, is that more biographical information is typically known about those who committed deadlier attacks (Silva & Capellan, 2019).¹⁶ All that being said, this is the first study that has attempted to identify sexual frustration problems among a large sample of mass shooters, so it is possible that some perpetrators with this problem were missed. Another limitation is that this study coded sexual frustration problems as a binary variable, which does not fully account for variation in frequency or severity. In prior research, similar approaches have been used to code a wide range of strains, frustrations, and stressors in mass shooters’ lives (Levin & Madfis, 2009; Newman et al., 2004; Peterson & Densley, 2021; Silver et al., 2018), but more nuanced measures could be used in the future (Lankford, 2021). It is also important to emphasize that it would be impossible for any study to measure exactly how sexual frustration problems affected each perpetrator’s decision to attack. The same limitation applies to most factors in mass shooters’ lives because there is no perfect method for weighing the differential effects of life frustrations, mental health problems, suicidal tendencies, anger, and other important variables.

Conclusion

Though several mass killings by incels have received a great deal of attention in recent years, the overall phenomenon of sexually frustrated offenders seems much larger. This study’s results suggest approximately one-third of public mass shooters had sexual frustration problems. Furthermore, sexually frustrated perpetrators committed many of the deadliest mass shootings in U.S. history, including attacks at Columbine, Virginia Tech, Sandy Hook, Orlando, Las Vegas, and Parkland. And although they attacked after our study was complete, the 2022 Buffalo and Uvalde shooters might also be added to this list. Initial reports suggest the former complained in his manifesto about the “problem with virtual relationships and porn” and the latter threatened to rape and kidnap girls he interacted with online.

As noted earlier, sexual frustration is certainly not the sole cause of mass shootings, but it often seems to be an important contributing factor. We found that sexually frustrated mass shooters were typically young, male, unmarried, single, childless, and unemployed—and before they engaged in mass killing, many were involved in other crimes, such as sex offending and domestic abuse. It is important to recognize, however, that at that point in their lives, it was not inevitable that they would eventually commit extreme violence. And if they had not become mass shooters, they still would have been influenced by sexual frustration, but we may never have heard of them or studied their criminal behavior.

This has concerning implications for aggression and violence more broadly. Are people who fit similar profiles—and who experience similar sexual frustration problems—also responsible for many non-lethal crimes? This is an important question that demands answers. Hopefully, additional research on the nature of sexual frustration, its effects on psychology and behavior, and the ways it could be reduced can lead to a healthier and safer society.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iDs

Adam Lankford

Jason R. Silva

Notes

Author Biographies

Adam Lankford is a Professor of Criminology & Criminal Justice at The University of Alabama. He is the author of two books and many peer-reviewed journal articles on various types of criminal behavior, including mass murder, mass shootings, and terrorism.

Jason R. Silva is an Assistant Professor in the Department of Sociology and Criminal Justice at William Paterson University. His research examines mass shootings, terrorism, and mass media. Silva’s recent publications have appeared in Aggression and Violent Behavior, American Journal of Criminal Justice, Justice Quarterly, and Journal of Interpersonal Violence.

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