Cumulative and Co-Occurring Strains Among Mass Public Shooting Perpetrators: Implications for Violence Prevention

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Greene-Colozzi, M. Hunter Martaindale This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9315797/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract Background. Mass public shootings represent a significant source of fatal and nonfatal injury in the United States. This study examines patterns of strain among individuals who carried out these events, with attention to the prevalence, co-occurrence, and cumulative burden of stressors. Methods. Data were drawn from a database of mass public shootings in the United States from 1999 to 2024, comprising 171 incidents and 175 perpetrators. Information was collected using a structured, multi-source approach including official records, secondary reports, and triangulated media sources. Eighteen dichotomous indicators of strain were coded. Descriptive statistics assessed prevalence and cumulative strain, and phi coefficients examined pairwise associations. Results. Perpetrators experienced multiple, overlapping forms of strain (mean = 4.78; SD = 2.78). Psychiatric concerns, job-related difficulties, and interpersonal stressors were most common. Strains frequently co-occurred, with strong associations among interpersonal and psychological factors and between structural stressors and ideological motivations. Most perpetrators experienced multiple concurrent stressors, indicating that these events rarely are preceded by a single, isolated grievance. Conclusions. Mass public shootings are better understood as the result of cumulative and co-occurring strains rather than isolated risk factors. Injury and violence prevention efforts may be strengthened by emphasizing patterns of stressors, early identification, and coordinated, systems-level responses, including threat assessment. mass public shootings violence prevention injury epidemiology risk factors strain behavioral warning signs threat assessment cumulative risk Figures Figure 1 Introduction Mass public shootings remain a persistent public health concern in the United States, resulting in significant loss of life, nonfatal injury , psychological trauma, and long-term disruption to affected communities [ 1 , 2 ]. Beyond the immediate casualties, these events generate widespread fear and impose substantial social and economic costs [ 1 , 3 ]. As such, identifying opportunities for prevention has become a critical priority for public health systems [ 1 ]. A growing body of research has examined the characteristics and antecedents of individuals who carry out mass public shootings [ 4 , 5 ]. Prior studies have identified a range of stressors and warning behaviors, including interpersonal conflicts, employment and financial difficulties, experiences of rejection or marginalization, and mental health concerns [ 4 – 7 ]. Importantly, this work suggests that perpetrators rarely experience a single, isolated stressor [ 6 , 7 ]. Rather, multiple grievances and life stressors often precede acts of targeted violence [ 6 , 8 ]. Prior research also has highlighted variation across types of mass public shooters, with differences in motivations, planning, and behaviors [ 4 , 7 ]. These studies further suggest, however, that common social and psychological pathways may underlie these events across offender types [ 4 , 7 ]. Despite these advances, much of the existing literature has focused on identifying and cataloging individual risk factors [ 6 ], often examining them in isolation. Comparatively less attention has been paid to how these stressors co-occur or accumulate within individuals [ 5 , 6 ]. As a result, there is limited empirical understanding of the broader patterns of strain that may characterize perpetrators, including whether certain types of stressors tend to cluster together and how the cumulative burden of strain varies across individuals [ 5 , 6 ]. Conceptually, these stressors can be understood as forms of strain, broadly defined as adverse experiences or perceived grievances that contribute to psychological distress [ 9 ]. Prior theoretical work has emphasized the importance of cumulative strain in understanding mass violence [ 9 ]. Levin and Madfis proposed a sequential model in which chronic, uncontrolled, and acute strains accumulate over time, ultimately contributing to the planning and execution of mass attacks [ 8 ]. Empirical research examining the cumulative and co-occurring nature of strain among mass public shooters, however, remains limited [ 5 , 6 ]. The present study addresses this gap by examining patterns of strain among individuals who carried out mass public shootings. Specifically, we (1) describe the prevalence of a range of identified grievances, (2) assess the extent to which these grievances co-occur, and (3) examine the cumulative burden of strain across perpetrators. By identifying patterns of overlapping and accumulating stressors, this study aims to inform injury and violence prevention efforts that move beyond single risk factors and instead consider the broader constellation of experiences that may signal elevated risk. Methods Data source and sample Data for this study were drawn from a database of mass public shootings developed by the research team using a structured, multi-source data collection process. The database includes incidents occurring in the United States between 1999 and 2024 and was designed to systematically capture information on perpetrator characteristics, behaviors, and pre-attack experiences. Mass public shootings were defined as incidents of targeted violence occurring in public or populated locations, involving one or more shooters and multiple victims (fatalities and/or injuries), within a single 24-hour period. Victims and locations were selected either at random or for symbolic value, and incidents associated with gang activity or organized terrorist actions were excluded [ 10 ]. Cases meeting these criteria were restricted further to those in which there was confirmed evidence of pre-attack leakage or warning behaviors, as established in prior research [ 11 ]. This resulted in a final sample of 171 incidents involving 175 perpetrators, including four cases with multiple offenders. Data collection and coding procedures Data were collected using a three-tiered approach designed to maximize completeness and reliability of available information. Tier 1 sources consisted of official records, including law enforcement documents and court records, obtained through systematic public records requests. In total, more than 280 requests were submitted, yielding over 143,000 pages of official documentation. Tier 2 and Tier 3 sources were identified through structured open-source searches using targeted keywords across 29 search engines and media platforms. Tier 2 sources included secondary summary and interpretive materials, such as after-action reports, case studies, and agency press releases. Tier 3 sources consisted of media reports, which were triangulated across at least three independent, reputable outlets for each variable to ensure accuracy and completeness. The full database consisted of more than 153,000 pages of records across the three tiers. Each case was initially coded by a trained research assistant using a standardized coding instrument. Cases then were independently reviewed by one of the study authors. Following this review, a coding verification memo was prepared and evaluated by a second author. Any discrepancies identified during the review process were discussed and reconciled, and coding decisions were updated prior to final inclusion in the dataset. Measures The present study focuses on 18 dichotomous indicators of strain, representing a range of stressors, grievances, and motivations identified in the literature, including analyses of targeted violence [ 12 – 14 ]. Each indicator was coded as present (1) when sufficient evidence was available, or absent (0) when confirmatory evidence indicated that the strain was not present. In cases where available information was insufficient to determine whether a strain was present, the variable was coded as missing. A cumulative strain index was created by summing the number of strain indicators present for each perpetrator, resulting in a count variable representing the total number of identified strains. Higher values on this index indicate greater exposure to multiple, co-occurring stressors. Analytic approach Descriptive statistics were used to examine the prevalence of individual strain indicators and the distribution of cumulative strain across perpetrators. Pairwise associations between strain indicators were assessed using phi coefficients, which are appropriate for dichotomous variables. Analyses were conducted using pairwise deletion to account for missing data. Confirmatory evidence of absence was relatively uncommon for several variables, resulting in limited variability and preventing the estimation of some pairwise associations. Accordingly, analyses focused on interpretable associations based on available data. Results The sample consisted of 175 perpetrators involved in 171 mass public shooting incidents. The majority of perpetrators were male (94.9%) and White (62.3%). Ages ranged from 12 to 88 years (mean = 32.9 years). Incidents most frequently occurred in schools (24.6%) and workplaces (21.6%). Prevalence of strain indicators Table 1 presents the prevalence of identified strain indicators among perpetrators. Psychiatric concerns were the most frequently observed strain (64.6%), followed by job-related difficulties (51.4%), familial troubles (50.3%), and relationship problems (41.1%). School-related difficulties (34.3%), bullying (30.3%), and financial strain (26.9%) also were commonly identified. Less frequently observed strains included ideological motivations (18.3%), fame-seeking (16.6%), religious grievances (12.0%), and homophobia (8.6%). Table 1 Prevalence of Identified Strain Indicators Among Perpetrators (N = 175) Strain Indicator n % Psychiatric concerns 113 64.6 Job troubles / loss 90 51.4 Familial troubles / loss 88 50.3 Relationship troubles / loss 72 41.1 School troubles / loss 60 34.3 Bullying 53 30.3 Financial troubles / loss 47 26.9 Conflict with friends / peers 44 25.1 Trauma / abuse 39 22.3 Social rejection 37 21.1 Inadequacy 37 21.1 Racism 34 19.4 Ideological motivation 32 18.3 Fame-seeking 29 16.6 Religious grievance 21 12.0 Homophobia 15 8.6 Misogyny 13 7.4 Other 8 4.6 Note. Percentages are based on the total sample (N = 175). Indicators were coded as present when sufficient evidence was available; absence was coded only when confirmatory evidence indicated the strain was not present. Cases lacking sufficient information were coded as missing. [INSERT FIGURE 1 ABOUT HERE] Co-occurring strain Analyses of pairwise associations revealed several patterns of co-occurring strain (Table 2 ). Interpersonal stressors were strongly interrelated, with relationship problems and familial troubles exhibiting a perfect association in cases with complete data (φ = 1.00, p < .001), and both demonstrating moderate associations with financial strain (φ = .55–.56). Table 2 Pairwise Associations Between Selected Strain Indicators Among Perpetrators Strain Pair φ p-value n Relationship problems – Familial troubles 1.00 < .001 40 Relationship problems – Psychiatric concerns 0.70 < .001 52 Familial troubles – Psychiatric concerns 0.70 < .001 69 Financial strain – Psychiatric concerns 0.56 < .001 35 Relationship problems – Financial strain 0.56 .002 29 Familial troubles – Financial strain 0.55 .004 25 Job-related difficulties – Ideological motivation 0.55 .006 23 Financial strain – Ideological motivation 0.67 .024 11 Note. φ = phi coefficient. Values reflect pairwise associations between dichotomous indicators. Analyses were conducted using pairwise deletion; therefore, sample sizes vary across comparisons. Only statistically significant and interpretable associations are shown. Interpersonal strains also were closely linked to psychiatric concerns. Relationship and familial difficulties each showed strong positive associations with psychiatric concerns (φ = .70, p < .001), and financial strain similarly was associated with psychiatric concerns (φ = .56, p < .001). Additional associations connected structural stressors to ideological motivations. Job-related difficulties were moderately associated with ideological motivation (φ = .55, p = .006), and financial strain also demonstrated a positive association with ideological motivation (φ = .67, p = .024). These estimates were based on smaller subsamples, and limited variability in some indicators prevented the estimation of several additional pairwise associations. [INSERT Table 2 ABOUT HERE] Cumulative strain Perpetrators experienced multiple strains, with a mean cumulative strain score of 4.78 (SD = 2.78) and a median of 4. The number of identified strains ranged from 1 to 14, with the majority of perpetrators (74.9%) experiencing between 2 and 7 stressors. As shown in Fig. 1 , the distribution of cumulative strain indicates that perpetrators typically experienced multiple, co-occurring grievances rather than isolated stressors. [INSERT FIGURE 1 ABOUT HERE] Discussion This study examined patterns of strain among individuals who carried out mass public shootings, with particular attention to the co-occurrence and cumulative burden of stressors. The findings indicate that perpetrators experienced multiple, overlapping forms of strain rather than isolated grievances. Several types of strain were especially prevalent, including psychiatric concerns, employment-related difficulties, and interpersonal stressors such as family and relationship problems. These strains also frequently co-occurred, with particularly strong associations observed among interpersonal and psychological factors. These findings suggest that mass public shooters are characterized not by a single precipitating factor, but by a combination of overlapping stressors that accumulate over time. A central finding of this study is that perpetrators experienced cumulative strain rather than isolated stressors, highlighting the limitations of single-factor explanations for mass public shootings. Perpetrators commonly experienced multiple forms of strain, many of which co-occurred. This pattern is consistent with prior theoretical work suggesting that different forms of strain, including chronic, uncontrolled, and acute stressors, accumulate and interact over time in ways that contribute to mass violence [ 8 ]. This finding also aligns with broader theories of strain, which posit that exposure to multiple stressors can increase pressure on individuals and heighten the likelihood of extreme behavioral responses [ 9 ]. These findings provide empirical support for cumulative strain frameworks and underscore the importance of understanding mass public shootings as the result of multiple, overlapping stressors rather than a single precipitating factor. In addition to the cumulative burden of strain, the findings also highlight patterns of co-occurring stressors. As these results indicate, strains were not experienced independently among perpetrators, although not all stressors co-occurred consistently or randomly. The strongest cluster of co-occurring strains involved psychiatric and interpersonal factors, particularly family and relationship troubles or loss. Perpetrators who experienced these interpersonal stressors also commonly experienced psychiatric difficulties, which may have limited their ability to cope with these events. Another pattern emerged between structural and ideological strains, such that perpetrators experiencing job-related or financial difficulties also were more likely to exhibit ideological motivations that could reframe the sources of these experiences. These findings underscore the importance of examining not only the number of strains present but also how they co-occur, as these patterns may shape how strain manifests in mass violence. Taken together, the findings of this study have important implications for how risk of violence and injury is understood, identified, and assessed. Current approaches often rely on a checklist mentality that focuses on individual warning signs and risk factors. As a result, these approaches may overlook patterns and clusters that reflect a cumulative burden of strain, increasing the likelihood that individuals respond to these pressures through extreme violence. Understanding this collective burden may improve the identification of individuals at risk for mass public shootings and support earlier intervention. It also may strengthen prevention efforts by informing systems-level responses, such as threat assessment approaches. This study is subject to several limitations that warrant acknowledgment. First, data were derived from available records, which varied in completeness across cases. Although efforts were made to ensure cases were as complete as possible, it is possible that the prevalence of some stressors in the present study is underestimated. Second, the lack of confirmatory evidence that stressors were not present, combined with missing data, limited the ability to estimate associations between some strains. As a result, additional significant associations between strains may not have been captured. Third, because this study focused on mass public shootings, and specifically on cases in which perpetrators demonstrated observable warning behaviors and communications, the findings may not be generalizable to other forms of violence. Finally, the absence of a comparison group limits the ability to assess whether similar patterns of strain are present among individuals who do not engage in mass violence. Conclusions These findings have important implications for injury and violence prevention. Practitioners should move beyond relying solely on individual warning signs and instead assess patterns of stressors across domains. In practice, this means attending to combinations of interpersonal, psychological, and structural stressors and considering their cumulative burden. This approach may help identify individuals at risk earlier and support more timely and targeted intervention. Integrating these considerations into existing assessment processes can strengthen prevention efforts and inform coordinated, systems-level responses. Public awareness also is critical, as individuals in the community often are the first to observe concerning behaviors. Educating the public to recognize patterns of cumulative stressors, rather than isolated warning signs, may improve reporting and help bring individuals of concern to the attention of practitioners. Effective prevention also requires coordinated, systems-level approaches. This includes the involvement of multiple stakeholder groups, such as education, workplaces, law enforcement, and mental health. Interdisciplinary coordination is essential for effective threat assessment and management, as is ensuring that team members have access to training and resources to recognize patterns of stressors that may precede mass violence. Policymakers can support these efforts by ensuring the availability of training and by investing in the development and sustainability of these teams’ infrastructure through funding and other resources. Together, these approaches underscore the importance of coordinated, multi-level strategies to prevent mass public shootings. Declarations Ethics approval and consent to participate This study used secondary data derived from publicly available sources and official records and did not involve direct interaction with human participants. As such, it was determined to be exempt from institutional review board approval. Consent for publication Not Applicable Availability of data and material The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request. Competing interests The authors declare that they have no competing interests. Funding This study was funded in part by the U.S. Department of Homeland Security’s Center for Prevention Programs and Partnerships, Opportunity No. DHS-24-TTP-132-00-99. Authors' contributions JS, EGC, and MHM contributed to the conceptualization of the study and data curation. JS and EGC conducted the formal analysis. JS drafted the manuscript. EGC and MHM contributed to reviewing and editing the manuscript. All authors read and approved the final manuscript. References Lowe SR, Galea S. The mental health consequences of mass shootings. Trauma Violence Abuse. 2017;18(1):62–82. 10.1177/1524838015591572 . Soni A, Tekin E. How do mass shootings affect community well-being? J Hum Resour. 2025;60(6):1841–80. 10.3368/jhr.1220-11385R1 . Fox JA. Trends in US mass shootings: Facts, fears, and fatalities. J Contemp Crim Justice. 2024;40(1):3–18. 10.1177/10439862231189987 . Capellan JA, Johnson J, Porter JR, Martin C. Disaggregating mass public shootings: A comparative analysis of disgruntled employee, school, ideologically motivated, and rampage shooters. J Forensic Sci. 2019;64(3):814–23. 10.1111/1556-4029.13985 . Silver J, Silva JR. A sequence analysis of the behaviors and experiences of the deadliest public mass shooters. J Interpers Violence. 2022;37(23–24):NP23468–94. 10.1177/08862605221078818 . Wichaidit W. Potential determinants of mass shooting perpetration and casualties: A systematic review. J Clin Diagn Res. 2023;17(10):LC06–13. 10.7860/JCDR/2023/61802.18520 . Kowalski RM, Leary MR, Hendley T, Ruble K, Chapman C, Chitty H, et al. K-12, college/university, and mass shootings: Similarities and differences. J Soc Psychol. 2021;161(6):739–53. 10.1080/00224545.2021.1900047 . Levin J, Madfis E. Mass murder at school and cumulative strain: A sequential model. Am Behav Sci. 2009;52(9):1227–45. 10.1177/0002764209332543 . Agnew R. Foundation for a general strain theory of crime and delinquency. Criminology. 1992;30(1):47–88. 10.1111/j.1745-9125.1992.tb01093.x . Schildkraut J, Elsass HJ. Mass shootings: Media, myths, and realities. Praeger; 2016. Greene-Colozzi EA. Mitigating the harm of public mass shooting incidents through situational crime prevention [dissertation]. New York, NY: City University of New York; 2022. National Threat Assessment Center. Protecting America’s Schools: A U.S. Secret Service Analysis of Targeted School Violence. U.S. Secret Service, Department of Homeland Security; 2019. National Threat Assessment Center. Averting Targeted School Violence: A U.S. Secret Service Analysis of Plots Against Schools. U.S. Secret Service, Department of Homeland Security; 2021. National Threat Assessment Center. Mass Attacks in Public Spaces: 2016–2020. U.S. Secret Service, Department of Homeland Security; 2023. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 06 May, 2026 Reviews received at journal 29 Apr, 2026 Reviewers agreed at journal 21 Apr, 2026 Reviewers agreed at journal 21 Apr, 2026 Reviews received at journal 20 Apr, 2026 Reviewers agreed at journal 20 Apr, 2026 Reviewers agreed at journal 19 Apr, 2026 Reviews received at journal 19 Apr, 2026 Reviewers agreed at journal 19 Apr, 2026 Reviewers agreed at journal 19 Apr, 2026 Reviewers invited by journal 09 Apr, 2026 Editor assigned by journal 09 Apr, 2026 Submission checks completed at journal 09 Apr, 2026 First submitted to journal 03 Apr, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9315797","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":623154074,"identity":"3cab597a-8582-4e40-b3d4-620ec7a952af","order_by":0,"name":"Jaclyn Schildkraut","email":"data:image/png;base64,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","orcid":"","institution":"Rockefeller Institute of Government","correspondingAuthor":true,"prefix":"","firstName":"Jaclyn","middleName":"","lastName":"Schildkraut","suffix":""},{"id":623154076,"identity":"2afa466a-a5e7-426b-b6c5-6915df45ef41","order_by":1,"name":"Emily A. 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Hunter Martaindale","email":"","orcid":"","institution":"Texas State University","correspondingAuthor":false,"prefix":"","firstName":"M.","middleName":"Hunter","lastName":"Martaindale","suffix":""}],"badges":[],"createdAt":"2026-04-03 19:23:21","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9315797/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9315797/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107146698,"identity":"d83a717b-0fec-4211-a365-652a8b87c71c","added_by":"auto","created_at":"2026-04-17 09:58:17","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":12127,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eDistribution of Cumulative Strain Among Perpetrators (N = 175)\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-9315797/v1/759389396fafdbf77549eb1c.png"},{"id":107146730,"identity":"ef1eab01-c69d-4aa6-9a7c-a76598ac6d9c","added_by":"auto","created_at":"2026-04-17 09:58:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":298977,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9315797/v1/38b6694a-0bd7-4a18-bf15-8fa6b0538785.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Cumulative and Co-Occurring Strains Among Mass Public Shooting Perpetrators: Implications for Violence Prevention","fulltext":[{"header":"Introduction","content":"\u003cp\u003eMass public shootings remain a persistent public health concern in the United States, resulting in significant loss of life, \u003cb\u003enonfatal injury\u003c/b\u003e, psychological trauma, and long-term disruption to affected communities [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Beyond the immediate casualties, these events generate widespread fear and impose substantial social and economic costs [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. As such, identifying opportunities for prevention has become a critical priority for public health systems [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eA growing body of research has examined the characteristics and antecedents of individuals who carry out mass public shootings [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Prior studies have identified a range of stressors and warning behaviors, including interpersonal conflicts, employment and financial difficulties, experiences of rejection or marginalization, and mental health concerns [\u003cspan additionalcitationids=\"CR5 CR6\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Importantly, this work suggests that perpetrators rarely experience a single, isolated stressor [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Rather, multiple grievances and life stressors often precede acts of targeted violence [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Prior research also has highlighted variation across types of mass public shooters, with differences in motivations, planning, and behaviors [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. These studies further suggest, however, that common social and psychological pathways may underlie these events across offender types [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eDespite these advances, much of the existing literature has focused on identifying and cataloging individual risk factors [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], often examining them in isolation. Comparatively less attention has been paid to how these stressors co-occur or accumulate within individuals [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. As a result, there is limited empirical understanding of the broader patterns of strain that may characterize perpetrators, including whether certain types of stressors tend to cluster together and how the cumulative burden of strain varies across individuals [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eConceptually, these stressors can be understood as forms of strain, broadly defined as adverse experiences or perceived grievances that contribute to psychological distress [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Prior theoretical work has emphasized the importance of cumulative strain in understanding mass violence [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Levin and Madfis proposed a sequential model in which chronic, uncontrolled, and acute strains accumulate over time, ultimately contributing to the planning and execution of mass attacks [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Empirical research examining the cumulative and co-occurring nature of strain among mass public shooters, however, remains limited [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eThe present study addresses this gap by examining patterns of strain among individuals who carried out mass public shootings. Specifically, we (1) describe the prevalence of a range of identified grievances, (2) assess the extent to which these grievances co-occur, and (3) examine the cumulative burden of strain across perpetrators. By identifying patterns of overlapping and accumulating stressors, this study aims to inform injury and violence prevention efforts that move beyond single risk factors and instead consider the broader constellation of experiences that may signal elevated risk.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003eData source and sample\u003c/h2\u003e \u003cp\u003eData for this study were drawn from a database of mass public shootings developed by the research team using a structured, multi-source data collection process. The database includes incidents occurring in the United States between 1999 and 2024 and was designed to systematically capture information on perpetrator characteristics, behaviors, and pre-attack experiences.\u003c/p\u003e \u003cp\u003eMass public shootings were defined as incidents of targeted violence occurring in public or populated locations, involving one or more shooters and multiple victims (fatalities and/or injuries), within a single 24-hour period. Victims and locations were selected either at random or for symbolic value, and incidents associated with gang activity or organized terrorist actions were excluded [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Cases meeting these criteria were restricted further to those in which there was confirmed evidence of pre-attack leakage or warning behaviors, as established in prior research [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. This resulted in a final sample of 171 incidents involving 175 perpetrators, including four cases with multiple offenders.\u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003eData collection and coding procedures\u003c/h3\u003e\n\u003cp\u003eData were collected using a three-tiered approach designed to maximize completeness and reliability of available information. Tier 1 sources consisted of official records, including law enforcement documents and court records, obtained through systematic public records requests. In total, more than 280 requests were submitted, yielding over 143,000 pages of official documentation.\u003c/p\u003e \u003cp\u003eTier 2 and Tier 3 sources were identified through structured open-source searches using targeted keywords across 29 search engines and media platforms. Tier 2 sources included secondary summary and interpretive materials, such as after-action reports, case studies, and agency press releases. Tier 3 sources consisted of media reports, which were triangulated across at least three independent, reputable outlets for each variable to ensure accuracy and completeness. The full database consisted of more than 153,000 pages of records across the three tiers.\u003c/p\u003e \u003cp\u003eEach case was initially coded by a trained research assistant using a standardized coding instrument. Cases then were independently reviewed by one of the study authors. Following this review, a coding verification memo was prepared and evaluated by a second author. Any discrepancies identified during the review process were discussed and reconciled, and coding decisions were updated prior to final inclusion in the dataset.\u003c/p\u003e\n\u003ch3\u003eMeasures\u003c/h3\u003e\n\u003cp\u003eThe present study focuses on 18 dichotomous indicators of strain, representing a range of stressors, grievances, and motivations identified in the literature, including analyses of targeted violence [\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Each indicator was coded as present (1) when sufficient evidence was available, or absent (0) when confirmatory evidence indicated that the strain was not present. In cases where available information was insufficient to determine whether a strain was present, the variable was coded as missing.\u003c/p\u003e \u003cp\u003eA cumulative strain index was created by summing the number of strain indicators present for each perpetrator, resulting in a count variable representing the total number of identified strains. Higher values on this index indicate greater exposure to multiple, co-occurring stressors.\u003c/p\u003e\n\u003ch3\u003eAnalytic approach\u003c/h3\u003e\n\u003cp\u003eDescriptive statistics were used to examine the prevalence of individual strain indicators and the distribution of cumulative strain across perpetrators. Pairwise associations between strain indicators were assessed using phi coefficients, which are appropriate for dichotomous variables. Analyses were conducted using pairwise deletion to account for missing data.\u003c/p\u003e \u003cp\u003eConfirmatory evidence of absence was relatively uncommon for several variables, resulting in limited variability and preventing the estimation of some pairwise associations. Accordingly, analyses focused on interpretable associations based on available data.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eThe sample consisted of 175 perpetrators involved in 171 mass public shooting incidents. The majority of perpetrators were male (94.9%) and White (62.3%). Ages ranged from 12 to 88 years (mean\u0026thinsp;=\u0026thinsp;32.9 years). Incidents most frequently occurred in schools (24.6%) and workplaces (21.6%).\u003c/p\u003e \u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003ePrevalence of strain indicators\u003c/h2\u003e \u003cp\u003eTable\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e presents the prevalence of identified strain indicators among perpetrators. Psychiatric concerns were the most frequently observed strain (64.6%), followed by job-related difficulties (51.4%), familial troubles (50.3%), and relationship problems (41.1%). School-related difficulties (34.3%), bullying (30.3%), and financial strain (26.9%) also were commonly identified. Less frequently observed strains included ideological motivations (18.3%), fame-seeking (16.6%), religious grievances (12.0%), and homophobia (8.6%).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePrevalence of Identified Strain Indicators Among Perpetrators (N\u0026thinsp;=\u0026thinsp;175)\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"3\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStrain Indicator\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003en\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e%\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003ePsychiatric concerns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e113\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e64.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eJob troubles / loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e90\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e51.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFamilial troubles / loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e88\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e50.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRelationship troubles / loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e72\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e41.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSchool troubles / loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e60\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e34.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eBullying\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e30.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFinancial troubles / loss\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e47\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e26.9\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eConflict with friends / peers\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e44\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e25.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eTrauma / abuse\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e39\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e22.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eSocial rejection\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eInadequacy\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e37\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e21.1\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRacism\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e34\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e19.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eIdeological motivation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e32\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e18.3\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFame-seeking\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e16.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eReligious grievance\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e21\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e12.0\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eHomophobia\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e15\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e8.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eMisogyny\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e13\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e7.4\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eOther\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e8\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c3\"\u003e \u003cp\u003e4.6\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"3\"\u003e\u003cb\u003eNote.\u003c/b\u003e Percentages are based on the total sample (N\u0026thinsp;=\u0026thinsp;175). Indicators were coded as present when sufficient evidence was available; absence was coded only when confirmatory evidence indicated the strain was not present. Cases lacking sufficient information were coded as missing.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003c/div\u003e\n\u003ch3\u003e[INSERT FIGURE 1 ABOUT HERE]\u003c/h3\u003e\n\u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003eCo-occurring strain\u003c/h2\u003e \u003cp\u003eAnalyses of pairwise associations revealed several patterns of co-occurring strain (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Interpersonal stressors were strongly interrelated, with relationship problems and familial troubles exhibiting a perfect association in cases with complete data (φ\u0026thinsp;=\u0026thinsp;1.00, p \u0026lt; .001), and both demonstrating moderate associations with financial strain (φ\u0026thinsp;=\u0026thinsp;.55\u0026ndash;.56).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePairwise Associations Between Selected Strain Indicators Among Perpetrators\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"char\" char=\".\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e \u003cp\u003eStrain Pair\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e \u003cp\u003eφ\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003ep-value\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003en\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRelationship problems \u0026ndash; Familial troubles\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e1.00\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e40\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRelationship problems \u0026ndash; Psychiatric concerns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e52\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFamilial troubles \u0026ndash; Psychiatric concerns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.70\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e69\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFinancial strain \u0026ndash; Psychiatric concerns\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u0026lt;\u0026thinsp;.001\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e35\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eRelationship problems \u0026ndash; Financial strain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.56\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.002\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e29\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFamilial troubles \u0026ndash; Financial strain\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.004\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e25\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eJob-related difficulties \u0026ndash; Ideological motivation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.55\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.006\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e23\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003eFinancial strain \u0026ndash; Ideological motivation\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c2\"\u003e \u003cp\u003e0.67\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e.024\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"char\" char=\".\" colname=\"c4\"\u003e \u003cp\u003e11\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003ctfoot\u003e \u003ctr\u003e\u003ctd colspan=\"4\"\u003e\u003cb\u003eNote.\u003c/b\u003e φ\u0026thinsp;=\u0026thinsp;phi coefficient. Values reflect pairwise associations between dichotomous indicators. Analyses were conducted using pairwise deletion; therefore, sample sizes vary across comparisons. Only statistically significant and interpretable associations are shown.\u003c/td\u003e\u003c/tr\u003e \u003c/tfoot\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eInterpersonal strains also were closely linked to psychiatric concerns. Relationship and familial difficulties each showed strong positive associations with psychiatric concerns (φ\u0026thinsp;=\u0026thinsp;.70,\u003c/p\u003e \u003cp\u003ep \u0026lt; .001), and financial strain similarly was associated with psychiatric concerns (φ\u0026thinsp;=\u0026thinsp;.56, p \u0026lt; .001).\u003c/p\u003e \u003cp\u003eAdditional associations connected structural stressors to ideological motivations. Job-related difficulties were moderately associated with ideological motivation (φ\u0026thinsp;=\u0026thinsp;.55, p = .006), and financial strain also demonstrated a positive association with ideological motivation (φ\u0026thinsp;=\u0026thinsp;.67, p = .024). These estimates were based on smaller subsamples, and limited variability in some indicators prevented the estimation of several additional pairwise associations.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e[INSERT Table \u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e ABOUT HERE]\u003c/h2\u003e \u003cdiv id=\"Sec12\" class=\"Section3\"\u003e \u003ch2\u003eCumulative strain\u003c/h2\u003e \u003cp\u003ePerpetrators experienced multiple strains, with a mean cumulative strain score of 4.78\u003c/p\u003e \u003cp\u003e(SD\u0026thinsp;=\u0026thinsp;2.78) and a median of 4. The number of identified strains ranged from 1 to 14, with the majority of perpetrators (74.9%) experiencing between 2 and 7 stressors. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, the distribution of cumulative strain indicates that perpetrators typically experienced multiple, co-occurring grievances rather than isolated stressors.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e[INSERT FIGURE \u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e ABOUT HERE]\u003c/h2\u003e \u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study examined patterns of strain among individuals who carried out mass public shootings, with particular attention to the co-occurrence and cumulative burden of stressors. The findings indicate that perpetrators experienced multiple, overlapping forms of strain rather than isolated grievances. Several types of strain were especially prevalent, including psychiatric concerns, employment-related difficulties, and interpersonal stressors such as family and relationship problems. These strains also frequently co-occurred, with particularly strong associations observed among interpersonal and psychological factors. These findings suggest that mass public shooters are characterized not by a single precipitating factor, but by a combination of overlapping stressors that accumulate over time.\u003c/p\u003e \u003cp\u003eA central finding of this study is that perpetrators experienced cumulative strain rather than isolated stressors, highlighting the limitations of single-factor explanations for mass public shootings. Perpetrators commonly experienced multiple forms of strain, many of which co-occurred. This pattern is consistent with prior theoretical work suggesting that different forms of strain, including chronic, uncontrolled, and acute stressors, accumulate and interact over time in ways that contribute to mass violence [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. This finding also aligns with broader theories of strain, which posit that exposure to multiple stressors can increase pressure on individuals and heighten the likelihood of extreme behavioral responses [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. These findings provide empirical support for cumulative strain frameworks and underscore the importance of understanding mass public shootings as the result of multiple, overlapping stressors rather than a single precipitating factor.\u003c/p\u003e \u003cp\u003eIn addition to the cumulative burden of strain, the findings also highlight patterns of co-occurring stressors. As these results indicate, strains were not experienced independently among perpetrators, although not all stressors co-occurred consistently or randomly. The strongest cluster of co-occurring strains involved psychiatric and interpersonal factors, particularly family and relationship troubles or loss. Perpetrators who experienced these interpersonal stressors also commonly experienced psychiatric difficulties, which may have limited their ability to cope with these events. Another pattern emerged between structural and ideological strains, such that perpetrators experiencing job-related or financial difficulties also were more likely to exhibit ideological motivations that could reframe the sources of these experiences. These findings underscore the importance of examining not only the number of strains present but also how they co-occur, as these patterns may shape how strain manifests in mass violence.\u003c/p\u003e \u003cp\u003eTaken together, the findings of this study have important implications for how risk of violence and injury is understood, identified, and assessed. Current approaches often rely on a checklist mentality that focuses on individual warning signs and risk factors. As a result, these approaches may overlook patterns and clusters that reflect a cumulative burden of strain, increasing the likelihood that individuals respond to these pressures through extreme violence. Understanding this collective burden may improve the identification of individuals at risk for mass public shootings and support earlier intervention. It also may strengthen prevention efforts by informing systems-level responses, such as threat assessment approaches.\u003c/p\u003e \u003cp\u003eThis study is subject to several limitations that warrant acknowledgment. First, data were derived from available records, which varied in completeness across cases. Although efforts were made to ensure cases were as complete as possible, it is possible that the prevalence of some stressors in the present study is underestimated. Second, the lack of confirmatory evidence that stressors were not present, combined with missing data, limited the ability to estimate associations between some strains. As a result, additional significant associations between strains may not have been captured. Third, because this study focused on mass public shootings, and specifically on cases in which perpetrators demonstrated observable warning behaviors and communications, the findings may not be generalizable to other forms of violence. Finally, the absence of a comparison group limits the ability to assess whether similar patterns of strain are present among individuals who do not engage in mass violence.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eThese findings have important implications for injury and violence prevention. Practitioners should move beyond relying solely on individual warning signs and instead assess patterns of stressors across domains. In practice, this means attending to combinations of interpersonal, psychological, and structural stressors and considering their cumulative burden. This approach may help identify individuals at risk earlier and support more timely and targeted intervention. Integrating these considerations into existing assessment processes can strengthen prevention efforts and inform coordinated, systems-level responses. Public awareness also is critical, as individuals in the community often are the first to observe concerning behaviors. Educating the public to recognize patterns of cumulative stressors, rather than isolated warning signs, may improve reporting and help bring individuals of concern to the attention of practitioners.\u003c/p\u003e \u003cp\u003eEffective prevention also requires coordinated, systems-level approaches. This includes the involvement of multiple stakeholder groups, such as education, workplaces, law enforcement, and mental health. Interdisciplinary coordination is essential for effective threat assessment and management, as is ensuring that team members have access to training and resources to recognize patterns of stressors that may precede mass violence. Policymakers can support these efforts by ensuring the availability of training and by investing in the development and sustainability of these teams\u0026rsquo; infrastructure through funding and other resources. Together, these approaches underscore the importance of coordinated, multi-level strategies to prevent mass public shootings.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study used secondary data derived from publicly available sources and official records and did not involve direct interaction with human participants. As such, it was determined to be exempt from institutional review board approval.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNot Applicable\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and material\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was funded in part by the U.S. Department of Homeland Security\u0026rsquo;s Center for Prevention Programs and Partnerships, Opportunity No. DHS-24-TTP-132-00-99.\u003c/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eAuthors\u0026apos; contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eJS, EGC, and MHM contributed to the conceptualization of the study and data curation. JS and EGC conducted the formal analysis. JS drafted the manuscript. EGC and MHM contributed to reviewing and editing the manuscript. All authors read and approved the final manuscript.\u003c/p\u003e\n"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eLowe SR, Galea S. The mental health consequences of mass shootings. Trauma Violence Abuse. 2017;18(1):62\u0026ndash;82. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1177/1524838015591572\u003c/span\u003e\u003cspan address=\"10.1177/1524838015591572\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSoni A, Tekin E. How do mass shootings affect community well-being? 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J Forensic Sci. 2019;64(3):814\u0026ndash;23. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/1556-4029.13985\u003c/span\u003e\u003cspan address=\"10.1111/1556-4029.13985\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSilver J, Silva JR. A sequence analysis of the behaviors and experiences of the deadliest public mass shooters. J Interpers Violence. 2022;37(23\u0026ndash;24):NP23468\u0026ndash;94. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1177/08862605221078818\u003c/span\u003e\u003cspan address=\"10.1177/08862605221078818\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWichaidit W. Potential determinants of mass shooting perpetration and casualties: A systematic review. 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Am Behav Sci. 2009;52(9):1227\u0026ndash;45. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1177/0002764209332543\u003c/span\u003e\u003cspan address=\"10.1177/0002764209332543\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAgnew R. Foundation for a general strain theory of crime and delinquency. Criminology. 1992;30(1):47\u0026ndash;88. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1111/j.1745-9125.1992.tb01093.x\u003c/span\u003e\u003cspan address=\"10.1111/j.1745-9125.1992.tb01093.x\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSchildkraut J, Elsass HJ. Mass shootings: Media, myths, and realities. Praeger; 2016.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eGreene-Colozzi EA. \u003cem\u003eMitigating the harm of public mass shooting incidents through situational crime prevention\u003c/em\u003e [dissertation]. New York, NY: City University of New York; 2022.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNational Threat Assessment Center. Protecting America\u0026rsquo;s Schools: A U.S. Secret Service Analysis of Targeted School Violence. U.S. Secret Service, Department of Homeland Security; 2019.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNational Threat Assessment Center. Averting Targeted School Violence: A U.S. Secret Service Analysis of Plots Against Schools. U.S. Secret Service, Department of Homeland Security; 2021.\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNational Threat Assessment Center. Mass Attacks in Public Spaces: 2016\u0026ndash;2020. U.S. Secret Service, Department of Homeland Security; 2023.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"injury-epidemiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"inep","sideBox":"Learn more about [Injury Epidemiology](https://injepijournal.biomedcentral.com)","snPcode":"40621","submissionUrl":"https://submission.nature.com/new-submission/40621/3","title":"Injury Epidemiology","twitterHandle":"@InjuryEpi","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"mass public shootings, violence prevention, injury epidemiology, risk factors, strain, behavioral warning signs, threat assessment, cumulative risk","lastPublishedDoi":"10.21203/rs.3.rs-9315797/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9315797/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground.\u003c/h2\u003e \u003cp\u003eMass public shootings represent a significant source of fatal and nonfatal injury in the United States. This study examines patterns of strain among individuals who carried out these events, with attention to the prevalence, co-occurrence, and cumulative burden of stressors.\u003c/p\u003e\u003ch2\u003eMethods.\u003c/h2\u003e \u003cp\u003eData were drawn from a database of mass public shootings in the United States from 1999 to 2024, comprising 171 incidents and 175 perpetrators. Information was collected using a structured, multi-source approach including official records, secondary reports, and triangulated media sources. Eighteen dichotomous indicators of strain were coded. Descriptive statistics assessed prevalence and cumulative strain, and phi coefficients examined pairwise associations.\u003c/p\u003e\u003ch2\u003eResults.\u003c/h2\u003e \u003cp\u003ePerpetrators experienced multiple, overlapping forms of strain (mean\u0026thinsp;=\u0026thinsp;4.78; SD\u0026thinsp;=\u0026thinsp;2.78). Psychiatric concerns, job-related difficulties, and interpersonal stressors were most common. Strains frequently co-occurred, with strong associations among interpersonal and psychological factors and between structural stressors and ideological motivations. Most perpetrators experienced multiple concurrent stressors, indicating that these events rarely are preceded by a single, isolated grievance.\u003c/p\u003e\u003ch2\u003eConclusions.\u003c/h2\u003e \u003cp\u003eMass public shootings are better understood as the result of cumulative and co-occurring strains rather than isolated risk factors. Injury and violence prevention efforts may be strengthened by emphasizing patterns of stressors, early identification, and coordinated, systems-level responses, including threat assessment.\u003c/p\u003e","manuscriptTitle":"Cumulative and Co-Occurring Strains Among Mass Public Shooting Perpetrators: Implications for Violence Prevention","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-17 09:57:45","doi":"10.21203/rs.3.rs-9315797/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-05-06T11:25:13+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-30T00:09:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"197382577023318262428791312474912309538","date":"2026-04-21T20:33:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"21815383173700566530957893735807732801","date":"2026-04-21T06:10:12+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-20T15:14:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"165306854055941820839060264063174081529","date":"2026-04-20T14:42:11+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"323595824584545942669611617023263879667","date":"2026-04-20T02:09:32+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-19T22:20:38+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"319644566454120230529662841463609154088","date":"2026-04-19T18:27:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"306847690883586628622405883749017716263","date":"2026-04-19T17:51:40+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-09T11:32:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-09T08:02:32+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-09T08:01:55+00:00","index":"","fulltext":""},{"type":"submitted","content":"Injury Epidemiology","date":"2026-04-03T19:08:35+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"injury-epidemiology","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"inep","sideBox":"Learn more about [Injury Epidemiology](https://injepijournal.biomedcentral.com)","snPcode":"40621","submissionUrl":"https://submission.nature.com/new-submission/40621/3","title":"Injury Epidemiology","twitterHandle":"@InjuryEpi","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"BMC/SO AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"93bc80f5-023b-4189-b68d-58507bd819d9","owner":[],"postedDate":"April 17th, 2026","published":true,"recentEditorialEvents":[{"type":"decision","content":"Revision requested","date":"2026-05-06T11:25:13+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-30T00:09:06+00:00","index":120,"fulltext":""}],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-15T15:39:41+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-17 09:57:45","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9315797","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9315797","identity":"rs-9315797","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}