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Do the Ages of Mass Shooters Matter? Analyzing the Differences Between Young and Older Offenders
Abstract
As the threat of public mass shootings continues to be on the forefront of Americans’ minds, it begs the question whether there are differences between young and older mass shooters. In general, earlier research suggests that young people are more likely than their older counterparts to commit crimes because of immaturity, lack of impulse control, rebelliousness, peer pressure, poor role models, and the influence of what they see on television or consume through other media content. When it comes to mass shooters, however, the answer to this question may depend on whether ‘‘young’’ offenders are defined using the legal age of adulthood or the scientific definition of when brain development typically reaches maturity. This study aims to determine whether significant differences exist between public mass shooters who were younger than or older than 18 years when they attacked, or younger than or older than 25 years when they attacked, by examining 88 offenders who struck in the United States from January 1982 to March 2018. Tests of statistical significance suggest that with both definitions, young mass shooters are more likely than older mass shooters to obtain their weapons illegally, attack at schools, have a reported history of animal abuse, and admit copying or being inspired by previous attackers. These results are interpreted in the context of previous scholarship, and recommendations are provided for future research.
... Many unknowns remain about the causes and prevention of these events. Mass shootings are a challenging type of crime to research due to their inherent heterogeneity (Fox & Levin, 2017;Lankford, 2015;Lankford & Hoover, 2019). Mass shootings are also rare events that involve only a handful of perpetrators, many of whom are ultimately killed or commit suicide shortly after the incident (Lankford, 2015). ...
Recent work by Allison and Klein examining violence and homicide introduced the concept of strained masculinity, a theoretical integration of general strain theory and hegemonic masculinity. Using qualitative data collection ( n = 63), the current study considers strained masculinity themes in the context of mass shootings and the gender gap. Findings demonstrated support for the prevalence of Allison and Klein’s themes in mass shootings. The men who committed mass shootings in our sample responded to challenges to their masculinity (62%), pursued hegemonic masculinity through “sport” (33%), and pursued hegemonic masculinity through controlling space (27%). In addition, qualitative analysis revealed overlaps in strained masculinity themes for mass shooting cases, demonstrating the complexity of this type of violence. There were six outlier cases identified that did not display strained masculinity, rather the perpetrators in these cases suffered from psychological or emotional troubles before opening fire. Overall, findings indicate that the integration of traditional criminology theories and gender theories is warranted.
... According to recent statistics [37], most of the past shooting attacks were carried out by male offenders, while data [38] also shows that they often used handguns as weapons. Another recent study [39] shows that young mass shooters are more likely than older. The design of the developed SG took into account these observations; hence the virtual shooter was assumed to be a young male armed with a handgun, as shown in Fig. 4. No blood effects or direct gunshots were employed in this simulation due to ethical and moral considerations. ...
An active shooting emergency requires an effective strategy to increase the chances of survival of the attacked population. Educational environments are one of the most common locations of such events. To reduce the impact of these disasters, several emergency plans have been developed and put in place. Traditionally, these emergency plans are taught to occupants using non-interactive videos, drills, etc. However, these conventional methods present many limitations regarding trainees' knowledge acquisition, engagement and self-efficacy. To overcome them, this paper presents the prototype of an immersive Virtual Reality (VR) Serious Game (SG) for counterterrorism training. A user-centred evaluation of the proposed training SG was conducted with 32 participants. The experiment aimed to investigate the impact of the proposed tool on participants' knowledge regarding the safest actions to take in case of an active shooter attack. Participants' intrinsic motivation and self-efficacy levels were also assessed before and after the VR-based training. Findings indicate that participants’ knowledge, intrinsic motivation, and self-efficacy significantly increased immediately after the training.
... According to recent statistics [37], most of the past shooting attacks were carried out by male offenders, while data [38] also shows that they often used handguns as weapons. Another recent study [39] shows that young mass shooters are more likely than older. The design of the developed SG took into account these observations; hence the virtual shooter was assumed to be a young male armed with a handgun, as shown in Figure 4. ...
Law enforcement and security services are facing a rising number of referrals involving concerns about an adolescent’s potential for extremist violence. Assessing and managing their risks requires a somewhat different approach than doing so with adults. While some risk and protective factors overlap, their significance varies at different stages, as do their mechanisms of action. Risk must be understood in its developmental context. The challenge is amplified because adolescents are concurrently undergoing significant biological, social/emotional, and cognitive changes. This article describes a developmentally informed approach to these assessments to help professionals better understand the complexities of adolescent behavior and to plan and provide more effective interventions. It introduces the general challenge of assessing risks related to violent extremism and the emergence of the Structured Professional Judgment model as a best practice approach. It goes on to define the contours of “developmentally informed assessment,” explaining why that perspective is necessary for a competent evaluation of an adolescent’s risk for extremist violence. The ensuing sections outline some of the key developmental constructs such as identity and psychosocial maturity and developmentally specific risk and protective factors to consider in those evaluations and conclude with a brief description and example of the risk formulation process.
Purpose
Factors that may influence risk and/or vulnerability to young people’s involvement in terrorism are currently unclear. Understanding the factors that contribute to a young person’s risk profile is a high priority for Youth Justice Services to enable the development of targeted interventions and subsequent risk reduction. The purpose of this study is to systematically identify and critically review studies relating to young peoples’ involvement in terrorism to understand potential risk and/or vulnerability factors and the implications for intervention.
Design/methodology/approach
Literature was evaluated using the systematic review method. Twelve papers were selected for the systematic review according to the inclusion criteria.
Findings
Twelve factors emerged that indicated relevance to terrorism by young people and were combined into five overarching themes: contextual, social, psychological factors, trauma and use of time.
Originality/value
This systematic review is one of the first of its kind relating to terrorism by young people. The reported findings will be valuable to practitioners seeking to understand the risk and vulnerability factors related to terrorism by young people and the implications for intervention. Directions for future research are explored.
Little is known about how defendant and victim religion influence juror decision-making outcomes in cases of extreme violent crime. The current study sought to examine whether defendant age (16- vs. 35-years-old), and defendant and victim religion (Christian vs. Muslim) influenced mock-jurors’ perceptions and verdict decisions in a religiously motivated mass shooting context. Participants (N = 321) read a mock-trial transcript describing the alleged mass shooting occurring at a place of worship. Participants were asked to provide verdict decisions, rate their perceptions of the defendant and victim, and answer questions related to religious bias and moral outrage toward the defendant. Overall, defendant religion influenced mock-jurors’ judgments such that Christian defendants received more guilty verdicts and less favourable perceptions than Muslim defendants, and victims were perceived more favourably when the defendant was Christian. Moreover, victim religion only influenced guilt ratings, such that mock-jurors were more likely to assign higher guilt ratings to a defendant when the victim was described as Muslim. Moral outrage partially mediated the effect of defendant religion and mock-juror perceptions of the defendant. The results of this study concluded that while defendant age and victim religion have little influence, defendant religion is greatly influential to juror decision-making. This research provides new insight regarding how influential defendant religion is in legal decision-making, and how moral outrage toward the defendant may have practical implications for legal decision-making.
Contagion and copycat behavior among mass killers is often discussed in the media when there are multiple attacks within a short span of time. Proximity in time, however, does not necessarily mean that one attack inspired another. This study examines the clearest cases of role modeling and fame seeking among mass killers in which the perpetrators personally acknowledged these types of influence and motivation in their own lives. Instead of simply categorizing potential copycat offenders in a “yes”/“no” binary fashion, it outlines many different types of influence, imitation, and inspiration and then provides evidence on perpetrators who represent examples of each type. Overall, findings suggest that most killers were not gaining insights into attack methodology from their role models, but rather were drawn to the prior perpetrators for a variety of personal reasons. Looking ahead, because of the frequency of mass killers citing previous perpetrators as role models or sources of inspiration, it is critical that media outlets give careful consideration to how they cover such incidents.
This document identifies the sources of firearms used in 52 school shootings (involving 54 perpetrators) during the twenty-five years from 1991 through 2015. The sample includes both single-victim and multi-victim shootings committed by secondary school, college, and aberrant adult perpetrators.
Although animal cruelty is often described as a warning sign of future human violence, particularly in the prediction of multiple homicides, prior studies reveal mixed support for this notion and lack conceptual clarity in the measurement of such cruelty. This study investigates the quantity and quality of cruelty present in a sample of 23 perpetrators of school massacres from 1988 to 2012. Findings indicate that 43% of the perpetrators commit animal cruelty before schoolyard massacres and that the cruelty is usually directed against anthropomorphized species (dogs and cats) in an up-close manner. The implications of these findings for reducing false positive cases of cruelty are discussed.
Developmental theories suggest that affiliation with deviant peers and susceptibility to peer influence are important contributors to adolescent delinquency, but it is unclear how these variables impact antisocial behavior during the transition to adulthood, a period when most delinquent individuals decline in antisocial behavior. Using data from a longitudinal study of 1,354 antisocial youth, the present study examined how individual variation in exposure to deviant peers and resistance to peer influence affect antisocial behavior from middle adolescence into young adulthood (ages 14 to 22 years). Whereas we find evidence that antisocial individuals choose to affiliate with deviant peers, and that affiliating with deviant peers is associated with an individual's own delinquency, these complementary processes of selection and socialization operate in different developmental periods. In middle adolescence, both selection and socialization serve to make peers similar in antisocial behavior, but from ages 16 to 20 years, only socialization appears to be important. After age 20, the impact of peers on antisocial behavior disappears as individuals become increasingly resistant to peer influence, suggesting that the process of desistance from antisocial behavior may be tied to normative changes in peer relations that occur as individuals mature socially and emotionally.
This study provides basic information about criminal activity at different ages (with offence data collected from official records) for a representative group of Swedish males and females who were investigated, from the age of 10 to 30, in a longitudinal research programme. It details information about the subject population, the method by which crime records were collected, and the coding system used. Prevalence of criminal offences at different ages is described, together with analyses of the ages at which subjects usually began breaking the law, when they were most criminally active, what types of crimes they committed at different ages, and what type of sanctions they were sentenced to. The paper concludes with a discussion of the prevalence of crime.
Prior research describes the development of susceptibility to peer pressure in adolescence as following an inverted U-shaped curve, increasing during early adolescence, peaking around age 14, and declining thereafter. This pattern, however, is derived mainly from studies that specifically examined peer pressure to engage in antisocial behavior. In the present study, age differences and developmental change in resistance to peer influence were assessed using a new self-report instrument that separates susceptibility to peer pressure from willingness to engage in antisocial activity. Data from four ethnically and socioeconomically diverse samples comprising more than 3,600 males and females between the ages of 10 and 30 were pooled from one longitudinal and two cross-sectional studies. Results show that across all demographic groups, resistance to peer influences increases linearly between ages 14 and 18. In contrast, there is little evidence for growth in this capacity between ages 10 and 14 or between 18 and 30. Middle adolescence is an especially significant period for the development of the capacity to stand up for what one believes and resist the pressures of one's peers to do otherwise.
The crime of mass murder is surrounded by myth, false assumptions, and misinformation. It is frequently sensationalized in the press, while the complex motivations of the perpetrator are ignored or soon forgotten. The mass murderer is rarely a crazed killer who lashes out against his victims in a mindless frenzy of violence. This book examines not only the crime of mass murder, but also the complex motivations of the mass murderer, presenting a completely new method of categorizing and analyzing the crime and its perpetrator. The evolving nature of the crime is examined in the context of actual case histories of mass murder in America. Kelleher's insights will be of interest to criminologists and anyone interested in the sociology of crime.
Increasingly in America, fame is revered as the ultimate form of prestige-bearing success, and the distinction between fame and infamy seems to be disappearing. In this context, some rampage shooters succumb to “delusions of grandeur” and seek fame and glory through killing. The present study offers initial findings on the behavior of fame-seeking rampage shooters, and then tests for differences between offenders who explicitly sought fame and other offenders. The results suggest that fame-seeking rampage shooters have existed for more than 40 years, but they are more common in recent decades and in the United States than in other countries. Overall, fame-seeking offenders appear younger than other rampage shooters, and they kill and wound significantly more victims. Several empirical predictions are made about the expected frequency and characteristics of future rampage shootings.
Objective:
Model the global distribution of public mass shooters around the world.
Method:
Negative binomial regression is used to test the effects of homicide rates, suicide rates, firearm ownership rates, and several control variables on public mass shooters per country from 1966 to 2012.
Results:
The global distribution of public mass shooters appears partially attributable to cross-national differences in firearms availability but not associated with cross-national homicide or suicide rates.
Conclusion:
The United States and other nations with high firearm ownership rates may be particularly susceptible to future public mass shootings, even if they are relatively peaceful or mentally healthy according to other national indicators.
Although researchers have questioned their coverage and accuracy, the media routinely are used as sources of data on mass murder in the United States. Databases compiled from media sources such as newspaper and network news programs include the New York Police Department's Active Shooters file, the Brady Campaign Mass Casualty Shootings data set, and the Mother Jones database. Conversely, official crime data have been underutilized by researchers who study mass murder (for exceptions, see Duwe, 2007; Fox & Levin, 1998). In this study, we compare similarities and differences for mass murder cases in the United States as portrayed by selected mass media sources. Then, we turn our focus to a comparison of the Uniform Crime Reports' (UCR) Supplementary Homicide Report (SHR) and the National Incident-Based Reporting System (NIBRS). Our primary focus is on mass murders involving four or more fatalities-not including the perpetrator-that have occurred between 2001 and 2010. Implications for enhancing the comprehensiveness and quality of mass murder data with the goal of increasing their usefulness for guiding prevention and risk mitigation efforts also are discussed.
Previous research suggests that there are fundamental psychological and behavioral differences between offenders who commit murder and offenders who commit murder-suicide. Whether a similar distinction exists for rampage, workplace, and school shooters remains unknown. Using data from the 2010 NYPD report, this study presents results from the first regression analysis of all qualifying mass shooters who struck in the USA between 1966 and 2010 (N = 185). Findings suggest that there are fundamental differences between mass shooters who die as a result of their attacks and mass shooters who live. Patterns among offenders, the weapons they use, the victims they kill, and the locations they attack may have significant implications for scholars and security officials alike.
School shootings have become more common in the United States in recent years. Yet, as media portrayals of these ‘rampages’ shock the public, the characterisation of this violence obscures an important point: many of these crimes culminate in suicide, and they are almost universally committed by males. We examine three recent American cases, which involve suicide, to elucidate how the culture of hegemonic masculinity in the US creates a sense of aggrieved entitlement conducive to violence. This sense of entitlement simultaneously frames suicide as an appropriate, instrumental behaviour for these males to underscore their violent enactment of masculinity.
Mass murder—the sudden, explosive killing of a group of people—when committed by adults often is followed by the offender committing suicide. Recently in the United States, frequent cases of mass murder are reported as committed by adolescents. However, among juvenile mass murderers, there are no reported suicides (or attempts) by the offenders. This article provides a typology of mass murderers and offers a dynamic interpretation of the development of conscience and moral decisional capacity in adult and juvenile offenders. Preventive measures are explored along with methodological techniques that may distinguish between adult and juvenile mass murderers in their propensity to commit suicide after the events.
One of the few facts agreed on in criminology is the age distribution of crime. This fact has been used to criticize social theories of crime causation, to provide the foundation for other theories, to justify recent emphases on career criminals, and to support claims of superiority for longitudinal designs in criminological research. In the present paper, we argue that the age distribution of crime is sufficiently invariant over a broad range of social conditions that these uses of the age distribution are not justified by available evidence.
Homicides committed against supervisors and coworkers by disgruntled employees have grown at a disturbing rate in the American workplace. Increasingly, embittered employees and ex-employees are seeking revenge through violence and murder for alleged mistreatment on the job. This article examines patterns and trends in available data and presents a theoretical profile of those who kill at the work site. It suggests that the typical homicide of employers and coworkers is committed by a disgruntled, white, middle-aged male who faces termination or who has recently been fired. Recommendations are advanced for how employers might better respond to problem employees and to homicidal threats at the workplace. These include prevention strategies, such as giving higher priority to the role of human resources, affording employees due process protection against unfair terminations, and changing the importance attached to the meaning of work in people's lives.
Peer influence is regarded as one of the strongest determinants of juvenile delinquency and particularly adolescent substance use. A commonly held view is that social pressure from friends to use drugs and alcohol is a major contributor to substance use. Yet the notion of peer pressure, implied by the association between peer-group associations and drug behavior, is seldom tested empirically. As a crucial test of the group pressure model, this research examines the role of peer pressure in mediating the effect of differential association on individual use. Moreover, few studies examine the nature of the relationship between peers and substance use as it relates to the processes leading toand from use. Drawing on differential association and social learning theories, our research specifies the social processes (socialization, group pressure, social selection, and rationalization) which dictate particular causal pathways leading to and from substance use and then estimates the reciprocal influences among differential association, social pressure from peers, attitudes favorable toward substance use, and individual use. Using the 1977–1979 National Youth Survey panel data, we estimate a covariance structural equation model allowing for correlated measurement error. In the cross-sectional analyses, we find no main effects of overt peer pressure on substance use. Estimation of the reciprocal effects model also reveals that overt peer pressure does not significantly influence substance use and does not mediate the effect of differential association. Instead, the influences of socialization, social selection, and rationalization play significant roles in understanding substance use.
The prevalence of antisocial and delinquent behavior in juveniles has increased dramatically over the past decades, along with the prevalence of other health-endangering behaviors, such as substance use and suicide. These trends have been accompanied by increased levels of psychiatric admissions and special classroom placements in schools. It is posed that these changes reflect decreased levels of impulse control by children living in the U.S. This paper focuses on impulse control as it relates to antisocial and delinquent behavior in juveniles. It traces the development of these behaviors through their age-specific manifestations, and summarizes known social and biological risk factors. The paper examines how different risk factors impinge on the development of antisocial behavior at different points in the life cycle. Developmental sequences are reviewed leading to serious antisocial behavior or to assistance of the behavior. The interaction between developmental tasks and the emergence of antisocial behavior is considered. Critical, “sensitive” periods in development often intersect with the increased prevalence of risk factors at certain age periods of children, leading to the emergence or aggravation of antisocial behavior. The use of empirical developmental knowledge for screening of population of youngsters is highlighted. The paper closes by reviewing how treatment and preventive studies are affected by pre-existing risk factors, and then lists priority areas for future survey and process studies, and for improved intervention efforts.
The age specificity of time-space clusters of suicide was examined using National Center for Health Statistics data for 1978-84. Significant clustering of suicide occurred primarily among teenagers and young adults, with minimal effect beyond 24 years of age. Clustering was two to four times more common among adolescents and young adults than among other age groups.
Thirty adult mass murderers and 34 adolescent mass murderers in North America are compared on both offender and offense variables to delineate similarities and differences. Findings indicate a plethora of psychiatric disturbances and odd/reclusive and acting-out personality traits. Predisposing factors include a fascination with weapons and war among many of the adolescents and the development of a "warrior mentality" in most of the adults. Precipitating factors indicate a major rejection or loss in the hours or days preceding the mass murder. Results are interpreted through the lens of threat assessment for targeted violence (Borum, Fein, Vossekuil, & Bergland 1999), recognizing that a fact-based, dynamic behavioral approach is most useful for mitigating risk of such an extremely low-base-rate violent crime.
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