Article

Are Active Shootings Temporally Contagious? An Empirical Assessment

Authors:
Article

Are Active Shootings Temporally Contagious? An Empirical Assessment

If you want to read the PDF, try requesting it from the authors.

Abstract

“Active Shootings,” which include shootings in public, confined areas such as schools, often traumatize communities and attract intense media coverage. Proposed policy responses to the phenomenon, such as concealing information as to casualty counts and even the identities of shooters, often suppose that active shootings are “contagious,” in that previous occurrences can enhance the likelihood of subsequent occurrences. This study marks the first attempt at assessment of the contagiousness of the active shooting phenomenon, and deploys a statistical model—the series hazard model—that is well-suited to the substantive issue of contagion as well as the fine-grained nature of the active shooting data. Results indicate that the hazard of observed active shootings was a function of the number of active shootings that preceded them in the previous two weeks.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... Copycat effects are more straightforward, and typically refer to peoples' imitation of an original actor's modeled behavior (Helfgott, 2015;Lankford, 2016b;Meindl & Ivy, 2017). Contagion, on the other hand, is based on the notion that behaviors can "go viral" and spread through society like diseases, with increased likelihood of their occurrence either in the short term or long term (Gould, Jamieson, & Romer, 2003;Kissner, 2016;Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015). Although social contagion can include copycat effects as one way that behaviors spread, it can also be less direct. ...
... A great deal of prior research has found evidence of contagion and copycat effects in various types of aggressive behavior, violent crime, mass killings, and terrorism (Berkowitz & Macaulay, 1971;Dugan, LaFree, & Piquero, 2005;Kissner, 2016;Langman, 2017;Nacos, 2009;Schmidtke, Schaller, & Miller, 2002;Towers et al., 2015). But perhaps the most well-known example of media-induced contagion is the finding that when suicides are highly publicized by the media, that can lead to a temporary increase in suicide rates (Abrutyn & Mueller, 2014;Gould et al., 2003;Gould, Kleinman, Lake, Forman, & Midle, 2014;Niederkrotenthaler et al., 2010;Phillips, 1974;Wasserman, 1984). ...
... When mass shooters receive a tremendous amount of media attention, that can turn them into role models and de facto celebrities for other impressionable individuals, who then may be more likely to commit mass shootings of their own (Helfgott, 2015;Kissner, 2016;Langman, 2017;Lankford, 2016b;Larkin, 2009;Meindl & Ivy, 2017;Murray, 2017;Towers et al., 2015). These imitators are not always fame-seekers: Some may empathize with the original attackers' claims that violence is a justifiable response to their feelings of mistreatment and marginalization (Muschert, 2012;Muschert & Ragnedda, 2010), and thus have an urge to emulate them. ...
Article
Full-text available
Prior research has shown that many mass shooters have explicitly admitted they want fame and have directly reached out to media organizations to get it. These fame-seeking offenders are particularly dangerous because they kill and wound significantly more victims than other active shooters, they often compete for attention by attempting to maximize victim fatalities, and they can inspire contagion and copycat effects. However, if the media changes how they cover mass shooters, they may be able to deny many offenders the attention they seek and deter some future perpetrators from attacking. We propose that media organizations should no longer publish the names or photos of mass shooters (except during ongoing searches for escaped suspects), but report everything else about these crimes in as much detail as desired. In this article, we (1) review the consequences of media coverage of mass shooters, (2) outline our proposal, (3) show that its implementation is realistic and has precedent, (4) discuss anticipated challenges, and (5) recommend future steps for consensus building and implementation.
... Research indicates that intense and frequent news coverage given to mass shootingsand particularly to perpetrators-can have both contagious and incentivizing effects on would-be mass killers (Kissner, 2016;Lankford, 2016a;Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015), much in the same way that a highly publicized suicide can lead to an increase in suicides (Carey, 2016;Centers for Disease Control and Prevention, 1994;Gould, Wallenstein, & Davidson, 1989). ...
... Recent research found that approximately 30% of mass killings were potentially inspired by previous mass killings, with sensational and detailed media coverage being a possible factor for the copycat acts (Towers et al., 2015). Kissner (2016) found that active shootings appear contagious and likely to inspire other active shootings for at least 2 weeks. Zarembo (2016) argues that perpetrators "inhabit the same publicity-obsessed culture as everybody else. ...
... The evidence also lends verification for Buttry's (2015) argument that in the UCC coverage, the media "obliged" in providing "limelight" for another mass killer. This is indeed a disturbing conclusion given agendasetting theory and research showing a connection between news media coverage, fame seeking perpetrators, and the contagion effect (Kissner, 2016;Lankford, 2016a;Towers et al., 2015). ...
Article
Given the intense news coverage that mass shootings receive and recent findings on contagion effects, it is important to examine how news media organizations cover these crimes. While reporting the “who” of news is a standard journalistic practice, there is growing debate regarding the extent to which the perpetrators of mass shootings should be named, pictured, and discussed in news media coverage. Within the theoretical framework of agenda-setting, this study examined U.S. newspaper photographic coverage following three major school shootings. Through content analysis of 4,934 photographs from 9 days of newspaper coverage, this study made several key findings about the overall prominence of photo use, changes in photo use during the 3 days following mass shootings, and comparisons between photos of perpetrators and victims. In particular, the study found empirical evidence that on a photos-per-individual basis, the coverage gave more attention to perpetrators than to individual deceased victims by a ratio of 16 to 1. Given contagion effects, this study finding raises serious concerns about current practices in news media publication of perpetrator photos. Although the Society of Professional Journalists’ Code of Ethics encourages news media members to seek truth and report it, the code also emphasizes moral imperatives to “balance the public’s need for information against potential harms” and “avoid pandering to lurid curiosity.”
... Ultimately everyone expresses a resolve that something must be done to prevent mass killings from reoccurring. In the United States, however, there is a high probability that a similar tragedy will occur again in the near future (Kissner, 2016;Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015). ...
... As with high-profile suicides, when a mass killing occurs, there appears to be an increased risk that similar behaviors will occur. Some studies have found that following an initial mass killing or active shooting, another incident will occur within the next 13 to 14 days, on average (Kissner, 2016;Towers et al., 2015). Essentially, one attack appears to induce another-there is an imitative or "contagion" effect. ...
... There are a variety of other factors that may play a role as well, such as weapons availability, mental illness, family conflicts, work or school problems, social strains, or ideological motives (Langman, 2015;Lankford, 2016b;Levin & Madfis, 2009;Newman et al., 2004). However, when temporal clustering of mass killings is demonstrated (i.e., mass killings appear "contagious"; Kissner, 2016;Towers et al., 2015), the action may be considered imitative. ...
Article
A mass killing is a complex behavior that is the product of a range of variables. Recent research suggests one such variable by showing that when a mass killing occurs there is a heightened chance of another occurring in the near future. This increase in probability has been referred to as contagion and one possible mechanism for contagion may be generalized imitation. Generalized imitation requires the presence of some model to prompt imitation, and we suggest media reporting methods as a prominent model inspiring future mass killings. This article analyzes mass killings as the culmination of a sequence of thoughts and actions that are influenced by environmental events including media reports of mass killings. We then evaluate media reporting guidelines and research related to the prevention of suicide and other imitational behaviors to identify reactive and proactive strategies that could minimize the likelihood of one mass killing inducing another.
... The literature on violent crimes and mass shootings uses the terms copycat effects and social contagion to describe the spatio-temporal dependence of these incidents (see, e.g., Towers et al., 2015, Kissner, 2016, Lankford & Tomek, 2018, Loeffler & Flaxman, 2018, and Torrecilla et al., 2019. We adopt the definition of copycat crimes from (Helfgott, 2008, p. 377) stating that "[c]opycat crime is crime inspired by another crime that has been publicized in the news media or fictionally or artistically represented whereby the offender incorporates aspects of the original offense into a new crime" and follow Lankford and Tomek (2018) stating that "[…] the social contagion thesis suggests that perpetrators receive so much attention for their attacks that each high-profile killer ends up "infecting" the minds of other impressionable individuals." ...
... Nevertheless, we need to account for this feature of the data by using our second step GMM estimates to obtain valid standard errors. Towers et al. (2015), Kissner (2016), and Lankford and Tomek (2018) also study the temporal dependence of crime but do so at a higher frequency. Towers et al. (2015) use a self-excitation contagion model and find that school shootings are contagious for an average of 13 days. ...
... However, their model does not use the panel structure of their state-level data to eliminate unobserved heterogeneity. Kissner (2016) analyzes active shootings using a series hazard model and reports an increased hazard for 2 weeks after the initial shooting. In contrast, Lankford and Tomek (2018) do not find evidence for short-term contagion. ...
... Prior research has also documented contagion effects for less lethal acts in schools and other public spaces, with varying claims about their role in instigating future attacks (Garcia-Bernardo et al., 2018;Jetter and Walker, 2018;Kissner, 2016). Utilizing data on individuals actively engaged in killing or attempting to kill people in a confined and populated area (so-called "active shooters"), Kissner (2016) found that the risk of an active shooter event increased by 27% for each event occurring in the preceding two weeks. ...
... Prior research has also documented contagion effects for less lethal acts in schools and other public spaces, with varying claims about their role in instigating future attacks (Garcia-Bernardo et al., 2018;Jetter and Walker, 2018;Kissner, 2016). Utilizing data on individuals actively engaged in killing or attempting to kill people in a confined and populated area (so-called "active shooters"), Kissner (2016) found that the risk of an active shooter event increased by 27% for each event occurring in the preceding two weeks. Curiously, Kissner did not find a significant effect for shorter time periods (e.g., one week) and the result for the two-week period was only marginally significant at the 10 percent level. ...
... First, some studies assume that the public is generally aware of all mass killings, despite evidence that most do not make national news (Duwe, 2004). In addition, failing to account for transmission in the form of publicity may skew results in favor of finding evidence of contagion, since incidents may be clustered in time but not necessarily as a result of direct imitation or general contagion (Kissner, 2016;Towers et al., 2015;Towers et al., 2018). Albeit a secondary concern, the studies that do include measures of publicity typically rely exclusively on a single outlet (e.g., newspapers, television, or social media), which may not be indicative of all media coverage (Garcia-Bernardo et al., 2018;Jetter and Walker, 2018;Lankford and Tomek, 2018;Stack, 1989). ...
Article
Full-text available
Mass public shootings have generated significant levels of fear in recent years, with many observers criticizing the media for fostering a moral panic, if not an actual rise in the frequency of such attacks. Scholarly research suggests that the media can potentially impact the prevalence of mass shootings in two respects: 1) some individuals may be inspired to mimic the actions of highly publicized offenders; and 2) a more general contagion process may manifest as a temporary increase in the likelihood of shootings associated with a triggering event. In this study of mass shootings since 2000, we focus on short-term contagion, rather than imitation that can traverse years. Specifically, after highlighting the sequencing of news coverage prior and subsequent to mass shootings, we apply multivariate point process models to disentangle the correlated incidence of mass public shootings and news coverage of such events. The findings suggest that mass public shootings have a strong effect on the level of news reporting, but that news reporting on the topic has little impact, at least in the relative short-term, on the subsequent prevalence of mass shootings. Finally, the results appear to rule out the presence of strong self-excitation of mass shootings, placing clear limits on generalized short-term contagion effects.
... The literature on violent crimes and mass shootings uses the terms copycat effects and social contagion to describe the spatio-temporal dependence of these incidents (see, e.g., Towers et al., 2015, Kissner, 2016, Lankford & Tomek, 2018, Loeffler & Flaxman, 2018, and Torrecilla et al., 2019. We adopt the definition of copycat crimes from (Helfgott, 2008, p. 377) stating that "[c]opycat crime is crime inspired by another crime that has been publicized in the news media or fictionally or artistically represented whereby the offender incorporates aspects of the original offense into a new crime" and follow Lankford and Tomek (2018) stating that "[…] the social contagion thesis suggests that perpetrators receive so much attention for their attacks that each high-profile killer ends up "infecting" the minds of other impressionable individuals." ...
... Nevertheless, we need to account for this feature of the data by using our second step GMM estimates to obtain valid standard errors. Towers et al. (2015), Kissner (2016), and Lankford and Tomek (2018) also study the temporal dependence of crime but do so at a higher frequency. Towers et al. (2015) use a self-excitation contagion model and find that school shootings are contagious for an average of 13 days. ...
... However, their model does not use the panel structure of their state-level data to eliminate unobserved heterogeneity. Kissner (2016) analyzes active shootings using a series hazard model and reports an increased hazard for 2 weeks after the initial shooting. In contrast, Lankford and Tomek (2018) do not find evidence for short-term contagion. ...
Article
Full-text available
School shootings are often motivated by the perpetrators' desire for media attention and notoriety. As school shootings receive intense regional and national media coverage, a high likelihood for copycat attacks can be expected. We investigate whether a copycat effect can be detected in US state‐level school shooting data from 1990 to 2017. We do so by estimating spatio‐temporal panel count models and control for socio‐economic characteristics, as well as state and Federal gun control laws. Positive spatial and temporal dependence indicate that the risk for additional school shootings in the same and neighboring states increases after the initial attack.
... In addition, mass shootings are becoming more frequent in the United States (Cohen, Azrael, and Miller 2014). As such, US journalists are tasked with covering mass shootings on a regular basis; and, indeed, this type of coverage generates a great deal of news media attention (Kissner 2016). Given the rise in mass shootings and the intense media coverage, this research examines the opinions of US news workers regarding media coverage of mass shootings. ...
... While there are various definitions of what constitutes a "mass shooting," it is generally accepted that mass shootings occur in public places, are random and seemingly indiscriminate, and result in the death of four or more victims, not including the perpetrator (Follman, Aronsen, and Pan 2016). The often intense media scrutiny accompanying mass shootings (Kissner 2016) could be seen in April 2007 after a gunman killed 32 people on the Virginia Tech campus. Every major news outlet sent crews to the scene, creating what Kellner (2008) referred to as "one of the most highly-saturated media sites of all time." ...
Article
Full-text available
Using data from a national survey of US newspaper journalists (N = 1318), this study examines attitudes toward news coverage of mass shootings. Following Shoemaker and Reese’s hierarchical model, the analysis also considers how individual characteristics, journalistic practices, and organizational factors influence these attitudes. Participants generally agreed that coverage had become routine. Journalists were largely supportive of coverage of perpetrators and were ambivalent about acknowledging a relationship between media coverage and a contagion, or “copycat,” effect. A participant’s age was generally the strongest predictor of attitudes toward media reporting on mass shootings. Findings also indicate differences in attitude according to job title, role perception, and whether or not a journalist had covered a mass shooting. A majority of respondents appeared to favor traditional, “neutral” approaches to coverage of mass shootings; however, journalists also wanted to see more comprehensive reporting, including coverage of solutions and community resilience.
... Unfortunately this trend continues, with 23 school shootings occurring between January and May of 2018. Researchers have documented a ''contagion effect,'' in which mass shootings and school shootings increase in probability during the 2-week period following an incident* (Bond and Bushman 2017;Kissner 2016;Kostinsky et al. 2001;Towers et al. 2015). For instance, Kissner (2016) examined the frequencies of active shooter events in Chicago from 2000 to 2009 and observed temporal clustering within 2-week periods. ...
... Researchers have documented a ''contagion effect,'' in which mass shootings and school shootings increase in probability during the 2-week period following an incident* (Bond and Bushman 2017;Kissner 2016;Kostinsky et al. 2001;Towers et al. 2015). For instance, Kissner (2016) examined the frequencies of active shooter events in Chicago from 2000 to 2009 and observed temporal clustering within 2-week periods. Towers et al. examined mass shootings (i.e., shootings in which there are three or more victims) and school shootings (i.e., shootings carried out on school property during school hours) separately and found that school shooting incidents between 1998 and 2013 were associated with an average increase of 0.22 new incidents for an average of 13 days following the incident. ...
... These types of influence have been analyzed by scholars using a variety of terms, including "contagion," "imitation," "inspiration," and "copycat behavior" (Kissner, 2016;Langman, 2017Langman, , 2018Lankford & Madfis, 2018a,b;Meindl & Ivy, 2018;Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015). Although the precise effects are impossible to determine for every case, prior research findings indicate that these influences may increase some at-risk individuals' desires to attack at all, to kill for fame and attention, and/or to kill a large number of victims for a correspondingly larger amount of fame and attention (Kissner, 2016;Langman, 2017Langman, , 2018Lankford, 2016b;Lankford & Madfis, 2018a,b;Meindl & Ivy, 2018;Towers et al., 2015). ...
... These types of influence have been analyzed by scholars using a variety of terms, including "contagion," "imitation," "inspiration," and "copycat behavior" (Kissner, 2016;Langman, 2017Langman, , 2018Lankford & Madfis, 2018a,b;Meindl & Ivy, 2018;Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015). Although the precise effects are impossible to determine for every case, prior research findings indicate that these influences may increase some at-risk individuals' desires to attack at all, to kill for fame and attention, and/or to kill a large number of victims for a correspondingly larger amount of fame and attention (Kissner, 2016;Langman, 2017Langman, , 2018Lankford, 2016b;Lankford & Madfis, 2018a,b;Meindl & Ivy, 2018;Towers et al., 2015). For instance, sometimes the role model may primarily serve as inspiration, whereas in other cases, the role model is influential by vividly demonstrating that high-fatality killers of this type are consistently rewarded by the media with fame (Lankford, 2016b;Lankford & Madfis, 2018a,b;Meindl & Ivy, 2018). ...
Article
Research Summary: Public mass shootings in the United States have become substantially more deadly over time. We document this increase, offer a model to explain it, review supporting evidence for the model, and present new findings on offenders from 1966 to 2019. It appears that societal changes have led to more public mass shooters who are motivated to kill large numbers of victims for fame or attention, as well as to more shooters who have been directly influenced by previous attackers. They often spend extended time planning their attacks and are increasingly likely to acquire powerful weapons and develop specific strategies to enhance their lethality. Policy Implications: New policies should be aimed at addressing the aforementioned factors. For instance, the deadliest public mass shooters' desires for fame and attention might be countered by a change in media coverage policies. Additionally, the deadliest perpetrators' lengthy planning periods have been associated with more warning signs being reported to police, so that type of information could justify denying many potential attackers access to firearms through extreme risk protection orders and red flag laws.
... Poverty has been documented to be associated with the homicide rate, but, to our knowledge [7][8][9][10][11], its link with mass shootings has not be evaluated yet. Another population-level risk factor associated with mass murders is the "contagion effect," which refers to the phenomenon a murder may temporarily increase the probability of a similar event in the proximal future [12,13]. It remains unclear if such a contagious effect is triggered by increased attention, which may be reflected by the quantity of media coverage of the key event in the community. ...
... Kostinsky and colleagues reported the clustering of threats of school violence following the Columbine massacre was initiated by imitation [38]. Although an earlier study did not find the clustering of rampage murders when they examined the data from 1988-1999 [39], recent evidence did suggest this phenomenon when more data were extracted [12,13]. Taken together, these lines of evidence have shown the influence of media on clustering (or contagion) of mass shootings. ...
Article
Full-text available
Little is known regarding the time trend of mass shootings and associated risk factors. In the current study, we intended to explore the time trend and relevant risk factors for mass shootings in the U.S. We attempted to identify factors associated with incidence rates of mass shootings at the population level. We evaluated if state-level gun ownership rate, serious mental illness rate, poverty percentage, and gun law permissiveness could predict the state-level mass shooting rate, using the Bayesian zero-inflated Poisson regression model. We also tested if the nationwide incidence rate of mass shootings increased over the past three decades using the non-homogenous Poisson regression model. We further examined if the frequency of online media coverage and online search interest levels correlated with the interval between two consecutive incidents. The results suggest an increasing trend of mass shooting incidences over time (p < 0.001). However, none of the state-level variables could predict the mass shooting rate. Interestingly, we have found inverse correlations between the interval between consecutive shootings and the frequency of on-line related reports as well as on-line search interests, respectively (p < 0.001). Therefore, our findings suggest that online media might correlate with the increasing incidence rate of mass shootings. Future research is warranted to continue monitoring if the incidence rates of mass shootings change with any population-level factors in order to inform us of possible prevention strategies.
... Research on copycat violence and contagion effects has primarily focused on a few key issues. For instance, scholars have established that high profile perpetrators can inspire and influence subsequent perpetrators (Follman, 2019;Helfgott, 2015;Langman, 2018); that high profile incidents may increase the likelihood of subsequent incidents (Kissner, 2016;Towers et al., 2015); and that outsized media coverage of perpetrators makes these effects more likely (Lankford & Madfis, 2018;Meindl & Ivy, 2018;Sidhu, 2017). ...
... In recent years, copycat violence and contagion effects have become a major research focus (Follman, 2019;Helfgott, 2015;Kissner, 2016;Langman, 2018;Lankford & Madfis, 2018;Meindl & Ivy, 2018;Sidhu, 2017;Towers et al., 2015), but little attention has been paid to how much violent role models and copycats resemble each other. ...
Article
Two of the worst targeted attacks on American police officers in recent history occurred within eleven days of each other. Although it seems clear their proximity was not merely attributable to chance, the connection between these incidents, and the implications for understanding copycat violence, have never been fully explored. This study analyzes the perpetrators of these attacks from a “thresholds of violence” perspective, which suggests the first actor in a sequence is more likely to be disturbed and violence prone, while subsequent actors are typically less disturbed but more socially influenced. Results suggest the thresholds model has both merits and limits. The first attacker did have more psychological problems and violence in his past, and the second did seem more influenced by violent role models. However, there were also many similarities between them, and both attacked due to a combination of internal and external factors. If this study's findings are generalizable, higher risks of becoming a copycat offender may exist for individuals who have (1) personal similarities with previous attackers, (2) a history of psychological problems, (3) a history of interest in violent actors, and (4) recent escalation in their online behavior. Recommendations are offered for future research, offender profiling, and violence prevention.
... Interestingly, each study used different types of theories, and thus, it was not easy to categorize them into categories. "Contagion theory" was used in three studies (Kissner, 2016;S. Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015;S. ...
Article
Due to the devastating impact on victims and society, scholars have started to pay more attention to the phenomenon of mass shootings (MS) in the United States. While the extant literature has given us important insights, disparities in conceptualizations, operationalizations, and methods of identifying and collecting data on these incidents have made it difficult for researchers and audiences to come to a deeper and more comprehensive understanding of the characteristics of offenders, causes and consequences. Using a mixed-method systematic review, this study seeks to assess the state of scholarly research in journal articles regarding MS in the United States. Using SCOPUS as the search database, a total of 73 peer-reviewed journal articles on MS within the United States published between 1999 and 2018 were included in this study. This study finds the number of articles published on MS has increased dramatically between 1999 and 2018. Also, most of the MS studies tend to rely heavily on open-source data using the different definitions of MS. We further examined and discussed theoretical frameworks, methodology, and policy suggestions used in each study. Based on the findings of this study, we suggested implications for future research.
... By open source, I mean data that are generated from existing, unclassified sources, most often print or electronic media accounts. In the past two decades, open source data have been collected to study a wide variety of international crimes, including terrorism (LaFree et al. 2015a), bias crime (McDevitt et al. 2003), and school (Towers et al. 2015), police (Ross 2015), and mass shootings (Kissner 2016). Because these databases originate with open source media it is unsurprising that they generally follow the classic journalistic format of providing information on who is responsible for an attack, what happened, where and when did it happen, and how did it happen. ...
Article
Full-text available
The contributors to this inaugural issue of International Criminology were asked to reflect on the present state of comparative criminology and to speculate on whether it will become more prominent in the future. Progress in developing a coherent research specialization in international criminology over the past half-century has been uneven, with some elements making more rapid progress than others. There have also been surprises, as well as disappointments. In this article, I briefly consider the modern history of efforts to develop a comparative study of criminology. I focus on cross-national comparative research which is largely quantitative. I look at the development of this research by considering its progress along six fronts: (1) developing larger, more representative samples; (2) developing more refined theoretical conceptual schemes; (3) applying more sophisticated research methods; (4) developing new international crime data sources; (5) building longitudinal models; and (6) engaging global organizations in support. I conclude with some general observations.
... Although the coverage of perpetrators is negative in tone, it may still have many unintended consequences, such as making mass killings-as potential opportunities to become famous-and mass killers-as de facto celebrities-more appealing to a small fraction of audience members. The role of contagion and copycat effects as consequences of media coverage of mass killers has been heavily documented in the scholarly literature (Follman & Andrews, 2015;Gould & Olivares, 2017;Helfgott, 2015;Kissner, 2016;Langman, 2017;Lankford, 2016;Lankford & Madfis, 2018;Meindl & Ivy, 2017;Murray, 2017;Perrin, 2016;Sidhu, 2017;Towers, Gomez-Lievano, Khan, Mubayi, & Castillo-Chavez, 2015). Of course, psychologically healthy people do not commit mass shootings based on what they read or see in the news, but there are troubled and at-risk individuals who respond very differently (Follman & Andrews, 2015;Gould & Olivares, 2017;Helfgott, 2015;Langman, 2017;Lankford, 2016Lankford, , 2018Murray, 2017;Perrin, 2016;Sidhu, 2017). ...
Article
Full-text available
In recent years, major media organizations have wondered if their coverage of mass shooters actually increases the risk of future attacks, and have asked how their reporting could be improved. In response, 149 experts have called for media to stop publishing the names and photos of mass killers (except during ongoing searches for escaped suspects), but continue reporting the other details of these crimes as needed. Here, we review some of the most important scientific findings on (a) the nature of media coverage of mass killers, (b) its consequences, and (c) solutions that could help make this coverage safer, and summarize how new studies published in this special issue of American Behavioral Scientist add to this valuable knowledge base.
... Descriptive studies of active shooter events in schools and businesses have also been published Majeed et al., 2019;Martaindale et al., 2017;Schildkraut et al., 2018;Schildkraut & Muschert, 2014). Other research has examined media coverage of these events (Majeed et al., 2019;Schildkraut et al., 2018;Schildkraut & Muschert, 2014), and the possibility of contagion effects (Kissner, 2016;Lankford & Madfis, 2018;Meindl & Ivy, 2017;Towers et al., 2015). Researchers have additionally examined the impact of these shootings on survivors and communities (Jordan, 2003;Richardson et al., 1996;Shultz et al., 2014;Smith et al., 2019). ...
Article
Full-text available
Active shooter events have captured the public’s attention since the Columbine High School shooting in 1999. Although there has been research on various aspects of these events, only a single study has attempted to identify factors that are related to the number of people injured or killed in these events. This study was limited in that it only considered the presence or absence of a semi-automatic rifle. This paper expands on the existing research by examining several other factors that may impact the total number of people shot or killed during active shooter events.
... News agencies have been criticized for overdramatization and overexposure. For some would-be shooters, receiving media attention can motivate violence (Dietz, 1986;Kissner, 2016). Florea (2013), in particular, made the argument that children and teenagers internalize violence in the news differently than adults. ...
Article
Full-text available
In this study, I document how members of the public perceive active shooter risk in their communities and their perceptions of the effectiveness of common efforts to prevent and respond to active shooters. I further investigate how news media exposure shapes these perceptions. I applied Protection Motivation Theory (PMT) to explore how perceptions and news media exposure might shape self-protective actions taken by individuals and their households. Data were obtained in 2019 from a cross-sectional, state-representative sample of 668 Pennsylvania adults who completed a web survey. Those who perceived higher community active shooter risk and those who felt community prevention and preparation efforts were effective were more likely to take self-protective steps themselves. Increased news exposure through apps, social media, family and friends was associated with increased perceived risk and effectiveness of prevention and preparation strategies. These results suggest that self-selected news and news through personal ties are linked to active shooter perceptions while other news mediums, like television or radio broadcasts, are not. News exposure was largely unrelated to self-protection. Those who felt community efforts were effective in prevention or preparation, however, were more likely to take self-protective actions. This finding indicates that community efforts may be more influential than news media in directing personal behavior.
... Around the world, there has been a recent sharp increase in mass shootings (Gould & Olivares, 2017;Kissner, 2016;Silver, Simons, & Craun, 2018) and hate crimes and incidents (Gaudet, 2018). 4 Three main social processes may explain this increase in the prevalence and ideological legitimation of violence: (1) an upsurge in populist political positions which unite people around threatened identities, including extreme right-wing movements in North America, South America and in Europe) (Rousseau, Miconi, Frounfelker, Hassan, & Oulhote, 2020). ...
Article
Full-text available
This article introduces a thematic issue of Transcultural Psychiatry with selected papers from the McGill Advanced Study Institute in Cultural Psychiatry on "Pluralism and Polarization: Cultural Contexts and Dynamics of Radicalization," which took place June 20-22, 2017. The ASI brought together an interdisciplinary group scholars to consider the role of social dynamics, cultural contexts and psychopathology in radicalization to violent extremism. Papers addressed four broad topics: (1) current meanings and uses of the term radicalization; (2) personal and social determinants of violent radicalization, including individual psychology, interpersonal dynamics, and wider social-historical, community and network processes; (3) social and cultural contexts and trajectories of radicalization including the impact of structural and historical forces associated with colonization and globalization as well as contemporary political, economic and security issues faced by youth and disaffected groups; and (4) approaches to community prevention and clinical intervention to reduce the risk of violent radicalization. In this introductory essay, we revisit these themes, define key terms, and outline some of the theoretical and empirical insights in the contributions to this issue. Efforts to prevent violent radicalization face challenges because social media and the Internet allow the rapid spread of polarizing images and ideas. The escalation of security measures and policies also serves to confirm the worldview of conspiracy theory adherents. In addition to addressing the structural inequities that fuel feelings of anger and resentment, we need to promote solidarity among diverse communities by building a pluralistic civil society that offers a meaningful alternative to the violent rhetorics of us and them.
... Unlike the findings regarding "ecological determinants," the idea of imitation has received mixed empirical support in the literature. For instance, Kissner (2016) found that the occurrence of a mass public shooting significantly increased the hazard of experiencing another mass public shooting for 2 weeks. However, Lankford and Tomek (2017) found no evidence of such a short-term contagion effect. ...
Article
Full-text available
For the last 40 years, the general profile of mass public shooters has enjoyed enduring consensus by experts, and as a result, it has remained static over this time. However, a recent string of mass public shootings perpetrated by “atypical” offenders bring into question the stability of the characteristics, motivations, and methods employed by these offenders. The goal of this study is to examine the stability and change of these characteristics and behaviors over the last 32 years (1984–2015). Using an open-source database, this study compares mass public shootings in 2000–2015 time period to the attacks committed in 1984–1999. The results illustrate not only sharp increase in number of mass public shootings in the last 16 years but also a significant growth in the racial heterogeneity and background characteristics of these offenders, clearly marking a departure from the general accepted profile of mass public shooters and mass murderers. The results also point to key characteristics, and behaviors that have remained static during the analysis time. Additionally, this study explores the implications these changes and stability on crime prevention strategies, as well as strategies to mitigate the lethality of these attacks.
... Beyond simply documenting this influence, however, the article seeks to demonstrate the many variations of role-modeling, imitation, and inspiration. Most studies of mass shooting contagion and copycat effects have focused on establishing whether or not previous attackers influenced subsequent attackers, in what is essentially a binary fashion (Kissner, 2016;Lankford & Tomek, 2017;Towers et al., 2015). This is an important first step, and potential copycat cases could certainly be categorized as simply a "yes" if there was evidence of direct influence from a previous attacker, or "no" if there was no such evidence. ...
Article
Full-text available
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.
... It is not possible at this point, however, to fully distinguish the increase in the use of the concept from the evolution of this social and psychological phenomenon per se. In the last few years, there has been a sharp increase not only in mass shootings (Gould & Olivares, 2017;Kissner, 2016;Silver, Simons, & Craun, 2018) but also in hate crimes and incidents throughout the world and in Canada (ADL Fighting Hate for Good, 2019; Gaudet, 2018; U.S. Department of Justice, 2017). ...
Article
The upsurge in violent radicalization is associated with a global increase in social inequalities and conflicts related to different markers of identity. To date, literature on the factors associated with legitimizing violence toward others is cross-sectional and does not provide information on the possible change of this phenomenon over time. Such information is necessary to design primary prevention programs that are adapted to and address a rapidly evolving social context. We use a repeated cross-sectional study design to explore the association between sociodemographic characteristics and scores on the Sympathy for Violent Radicalization Scale (SVR) in Quebec (Canada) college students at 2 times points. Results from an online survey completed by students of 6 colleges in 2015 (n = 854) and 2017 (n = 702) indicate that although overall scores on the SVR scale remained stable, there were changes in the association between age, identity, and the outcome at the two time points. Specifically, scores on the SVR were significantly higher among younger students in 2017 than in 2015. In addition, in 2017 we observed a relationship between collective identity and SVR that was not present in 2015. These results align with other recent studies in Canada and the U.S. documenting the emergence of new forms of youth politicized bullying associated with race, ethnicity, and religion. A close monitoring of the phenomenon is warranted to both better understand the impact of populist policies on the increase in hate incidents and crimes and develop programs to address these forms of violence from a public health perspective. (PsycINFO Database Record (c) 2020 APA, all rights reserved).
... Other descriptive research has examined the correlates of the number of people shot and killed in these events (Blair et al., 2021b). Some research has examined media coverage of these events (Majeed et al., 2019;Schildkraut et al., 2017;Schildkraut and Muschert, 2014) and the possibility of contagion effects (Kissner, 2016;Lankford and Madfis, 2017;Meindl and Ivy, 2017;Towers et al., 2015). Researchers have additionally examined the impact of these shootings on survivors and communities (Jordan, 2003;Richardson et al., 1996;Shultz et al., 2014;Smith et al., 2019). ...
Article
Full-text available
Active shooter events have driven police to change how they respond to events where an attacker is actively engaged in killing civilians. This paper examines these changes through the lenses of Normal Accident Theory (NAT) and Resilience Engineering (RE). Our results show a police officer is shot in one out of every six active shooter events in the United States. We then apply RE to better understand how these shootings occur so that police can improve their ability to anticipate, monitor, and respond during these attacks. Implications for police training are discussed.
... We conduct this exercise because our initial choice of a seven-day time window for subsequent shootings may well be considered arbitrary, as it remains difficult to theorize how long a potential shooter would need to move from observing shooting news to engaging in a shooting themselves. The corresponding descriptive studies suggest substantial differences in planning horizons (e.g., see Vossekuil, 2004;Kissner, 2016;Gill et al., 2017;Langman, 2017;Capellan andGomez, 2018, andSilver et al., 2018). Varying the time horizon also allows us to explore whether our findings from Table 4 are specific to a seven-day time window. ...
Article
We study the potential effect of mass-shooting-related television news in the US on subsequent mass shootings from 2006–2017. To circumvent endogeneity, our identification strategy relies on unpredictable disasters in countries home to substantial numbers of US emigrants crowding out shooting news. Instrumental variable and reduced form regressions consistently suggest a positive and statistically significant effect. This result remains consistent throughout a battery of robustness checks. In terms of magnitude, a one standard deviation increase in shooting news raises mass shootings by approximately 73% of a standard deviation. We then explore potential mechanisms, broadly delineating (i) the ideation of murder, (ii) fame seeking, and (iii) behavioral contagion. The number of murders in general remains orthogonal to shooting news, and mass shootings are not more likely on days with predictable news pressure (e.g., during the Olympics or the Super Bowl). However, mass shootings are more likely after anniversaries of the most deadly historical mass shootings. Taken together, these results lend support to a behavioral contagion mechanism following the public salience of mass shootings.
... Although extensive media coverage of mass shootings may contribute to a contagion effect, in which other vulnerable individuals may identify with the shooters and find inspiration to carry out violent acts, conflicting conclusions exist in the literature [16]. Two studies suggest that an act of active shooting is likely to increase the risk of another mass shooting inspired by the previous event in the following 2 weeks [19,21]. Towers et al. reported significant evidence of new shooting events (0.22 (p = 0.0001)) as evidence of contagion in 2 weeks after a school shooting [19]. ...
Article
In line with previous research on suicide and social contagion, there has been widespread speculation that mass killings-which often involve suicidal offenders-are socially contagious for up to 14 days. This study tested these claims by making comparisons (i) between observed chronological clusters of mass killings in the United States from 2006 to 2013 and clusters in 500 simulations containing 116,000 randomly generated dates, and then (ii) between observed mass killings receiving varying levels of public attention. No evidence of short-term contagion was found, although longer term copycat effects may exist. Further scholarly and policy implications are discussed.
Article
Full-text available
The recent spate of mass public shootings in the United States raises important questions about how these tragic events might impact mass opinion and public policy. Integrating research on focusing events, contextual effects and perceived threat, this article stipulates that residing near a mass shooting should increase support for gun control by making the threat of gun violence more salient. Drawing upon multiple data sources on mass public shootings paired with large-N survey data, it demonstrates that increased proximity to a mass shooting is associated with heightened public support for stricter gun control. Importantly, the results show that this effect does not vary by partisanship, but does vary as a function of salience-related event factors, such as repetition, magnitude and recency. Critically, the core result is replicated using panel data. Together, these results suggest a process of context-driven policy feedback between existing gun laws, egregious gun violence and demand for policy change.
Chapter
This chapter offers a review of the literature of the nature of studying mass violence. It is often problematic, difficult, or nearly impossible due to small sample sizes, incomplete or inaccurate information, or discrepancies even deciding what exactly “mass violence” is. This chapter reviews the literature for methodological approaches, summarizes qualitative and quantitative methods and findings, and discusses the challenges of mass violence methodologies while also proposing solutions, suggestions, and directions for future research.
Article
This special issue includes: "Media Coverage of Mass Killers: Content, Consequences, and Solutions" by Adam Lankford and Eric Madfis; "Visually Reporting Mass Shootings: U.S. Newspaper Photographic Coverage of Three Mass School Shootings" by Nicole Smith Dahmen; "Covering Mass Murder: An Experimental Examination of the Effect of News Focus -- Killer, Victim, or Hero -- on Reader Interest" by Jack Levin and Julie B. Wiest; "Global Online Subculture Surrounding School Shootings" by Jenni Raitanen and Atte Oksanen; "Different Types of Role Model Influence and Fame Seeking Among Mass Killers and Copycat Offenders" by Peter Langman; "Narcissism, Fame Seeking, and Mass Shootings" by Brad J. Bushman; "Reducing Media-Induced Mass Killings: Lessons From Suicide Prevention" by James N. Meindl and Jonathan W. Ivy; "Don’t Name Them, Don’t Show Them, But Report Everything Else: A Pragmatic Proposal for Denying Mass Killers the Attention They Seek and Deterring Future Offenders" by Adam Lankford and Eric Madfis
Article
Given inconsistency across studies, it remains unclear how direct and vicarious experience with disaster shape views of police and views of local government. This study investigated the views of those with direct disaster experiences as well as exposure to terrorism news. Data were collected with a nationwide, online survey of 520 U.S. adults administered in 2017. Results indicated that having a direct experience with disaster was unrelated to views of police or local government. Those with more frequent terrorism news exposure through print news had lower opinions of police; those with more frequent exposure through national television news had more positive views. More frequent exposure to terrorism news in print and through friends or family was both associated with more trust in local government. Arrest history was a strong and consistent predictor of trust in local government, but not of views of the police.
Chapter
Mass shootings have been of interest and concern to a variety of experts including psychologists, sociologists, criminologists, public health experts, and policy makers. Journalists have tracked mass shooting events for a long time. Recently, mass shootings in public places have dominated the national dialogue about gun violence, gun control, and Second Amendment protections due to several mass pubic shootings in recent years that resulted in double-digit victim counts. Regardless of the why, it seems clear that the ability to identify and predict this behavior as early as possible is important, for the killer as well as the community.
Chapter
This concluding chapter presents a discussion of the findings as a whole along with the policy and theoretical implications that may be drawn from them. It also discusses emergent areas that may help prevent school rampage killing and suggests avenues for future research.
Chapter
This chapter examines biographical information about the shooters in the context of Bronfenbrenner's ecological systems theory. By using a qualitative approach to search for patterns and themes, this study offers a comprehensive evaluation of the presence or absence of many important factors that are found in the reporting of active and mass shooters. Rather than focusing on one major contributing factor, this chapter describes a number of factors, offers descriptive, specific accounts about individual shooters, and organizes a wealth of information from over 1200 news articles, books, and journals into a concise study for future research and evaluation.
Article
Full-text available
This study examined how news audience’s predispositions (value and outcome involvement, political and gun ownership identities) predicted perceived media bias in mass shooting coverage against gun owners and intention to participate in discursive activities concerning gun issues. Republicans, strong identifiers of gun ownership, and those who perceived the outcome of tightening gun ownership would affect their lives predicted perceptions of media bias. Strong party identifiers, gun ownership identifiers, and those who displayed outcome involvement predicted intention to participate in discursive activities. Perceived media bias was not found to predict the intention to participate in discursive activities concerning gun issues. The results extended the theoretical discussion of corrective action hypothesis and increased our understanding of both individual-level (personal involvement) and social-psychological level (social identities) factors relevant to biased media perception.
Article
White-collar crime and illegal political extremism share several characteristics with relevance to criminology. Neither is associated with lower socioeconomic status individuals, both involve perpetrators that rarely see themselves as criminal, and both face unique data challenges. Following Edwin Sutherland's influential research, the study of white-collar crime became a recognized specialization within criminology. Similarly, following the coordinated attacks of September 11, 2001, political extremism became increasingly accepted as a legitimate research topic in criminology. I explore several ways that the study of terrorism has influenced criminological research and how responses to terrorist attacks since 9/11 can help us understand policing. Terrorism research has vividly illustrated the socially constructed nature of crime, has encouraged researchers to see not only the deterrence potential of punishment but also its capacity to produce backlash, has accelerated cross-national criminology research, and has hastened the embrace of open sources as an important form of criminal justice data. Changes in policing following 9/11 and the resulting war on terror also provide critical insights into the extent to which policing depends on community trust and legitimacy. As with the embrace of white-collar crime nearly a century ago, mainstream criminology has been enriched by widening its scope to include political extremism.
Article
Full-text available
Objective Media recommendations for the reporting of events where one person or a small group kills multiple others in public settings have been developed recently by suicide prevention experts. Evidence on the effects of reports that are compliant or noncompliant with these recommendations is lacking. Methods We conducted a randomized controlled trial with n = 148 participants who were randomly assigned to read newspaper articles (A) on acts of terrorism assumed to be conducted by Islamist terrorists and not consistent with media recommendations, (B) the same articles differing only in their compliance with recommendations, or (C) articles of similar style that were about homicide. Islamophobia as well as suicidal ideation, stress, and mood were measured before reading the article (T1), immediately afterwards (T2), and one week later (T3). The primary hypothesis was that there is an increase in islamophobia after exposure to media portrayals not consistent with media recommendations. Results Compared to the control group, only participants reading media reports that were not consistent with media recommendations showed a short‐term increase in islamophobia. Conclusion These findings suggest that reporting on terrorism that is not consistent with media recommendations appears to increase islamophobia. In the context of reporting on Islamist terrorism, consistency with recommendations might help reduce negative attitudes toward Muslim minorities.
Article
Full-text available
Mass shootings at a Connecticut elementary school, a Colorado movie theater, and other venues have prompted a fair number of proposals for change. Advocates for tighter gun restrictions, for expanding mental health services, for upgrading security in public places, and, even, for controlling violent entertainment have made certain assumptions about the nature of mass murder that are not necessarily valid. This article examines a variety of myths and misconceptions about multiple homicide and mass shooters, pointing out some of the difficult realities in trying to avert these murderous rampages. While many of the policy proposals are worthwhile in general, their prospects for reducing the risk of mass murder are limited.
Article
Full-text available
A unique population of juveniles, serious and violent juvenile offenders (SVJOs), has emergedas a public concern. A corollary concern is the effect of the mass media on juveniles. Addressing both issues, an exploratory study of copycat crime and the media's role in copycat crime's generation among a sample of SVJOs is conducted. The study's goals are to measure the prevalence of self-reportedcopycat crime in SVJOs and examine the correlates of self-reported copycat criminal behaviors. Concerning prevalence, about one fourth of the juveniles reportedthat they have attempteda copycat crime. The correlates of copycat behavior include a set of media and peer-related attitudes. Academic and demographic characteristics are not foundto significantly relate to copycat crime. Additional research on specific media, such as video games, as well as offender/nonoffender comparisons is suggested.
Article
Full-text available
Notwithstanding the historical significance of the Columbine shooting, recent attention has shifted to college campuses following high-profile massacres at Virginia Tech and Northern Illinois University. In this article, the authors compile and discuss the recommendations most often put forth by task force reports published in the wake of these episodes. Although some proposals can increase the security and well-being of the campus community, others may be inappropriate and even carry unacceptable negative consequences. The problem rests partly in the implicit assumption that effective strategies for secondary schools will seamlessly translate to a college environment. However, campus shootings are not just Columbine graduated to higher education, as differences in assailant motivation and setting warrant divergent strategies for prevention and response.
Article
Full-text available
To explain the genesis of mass murder committed by students at their schools, the authors propose a five-stage sequential model in which several criminological theories (strain theory, control theory, and routine activities theory) are brought to bear collectively to demonstrate their cumulative effect. These stages are as follows: chronic strain, uncontrolled strain, acute strain, the planning stage, and the massacre. Long-term frustrations (chronic strains) experienced early in life or in adolescence lead to social isolation, and the resultant lack of prosocial support systems (uncontrolled strain) in turn allows a short-term negative event (acute strain), be it real or imagined, to be particularly devastating. As such, the acute strain initiates a planning stage, wherein a mass killing is fantasized about as a masculine solution to regain lost feelings of control, and actions are taken to ensure the fantasy can become reality. The planning process concludes in a massacre facilitated by weapons that enable mass destruction in schoolrooms and campuses, where students are closely packed together. Based on this analysis, prevention strategies are suggested.
Article
Full-text available
Few crimes command as much attention as mass murder. Depending on their magnitude and context, some of these incidents become enshrined as landmark historical events. Some give rise to substantial policy change. One such event in Australia was the Port Arthur Massacre that claimed 35 lives in 1996. Using a disaggregation strategy and intervention analysis, this article explores the impact of the Port Arthur massacre on subsequent homicides in Australia. The results of the analysis indicate that the Port Arthur incident appears to have had no lasting effect on homicide in Australia. However, there was an immediate increase in firearm homicides during the 5 days following the massacre. After this sudden increase, the incidence of homicide resumed its long-term downward trend. This sudden increase can be interpreted as evidence of a contagion effect, with the significant response by the Australian Government contributing to the incidence of homicide resuming its long-term trend, rather than continuing to increase.
Article
Full-text available
Background: Ecological studies support the hypothesis that suicide may be "contagious" (i.e., exposure to suicide may increase the risk of suicide and related outcomes). However, this association has not been adequately assessed in prospective studies. We sought to determine the association between exposure to suicide and suicidality outcomes in Canadian youth. Methods: We used baseline information from the Canadian National Longitudinal Survey of Children and Youth between 1998/99 and 2006/07 with follow-up assessments 2 years later. We included all respondents aged 12-17 years in cycles 3-7 with reported measures of exposure to suicide. Results: We included 8766 youth aged 12-13 years, 7802 aged 14-15 years and 5496 aged 16-17 years. Exposure to a schoolmate's suicide was associated with ideation at baseline among respondents aged 12-13 years (odds ratio [OR] 5.06, 95% confidence interval [CI] 3.04-8.40), 14-15 years (OR 2.93, 95% CI 2.02-4.24) and 16-17 years (OR 2.23, 95% CI 1.43-3.48). Such exposure was associated with attempts among respondents aged 12-13 years (OR 4.57, 95% CI 2.39-8.71), 14-15 years (OR 3.99, 95% CI 2.46-6.45) and 16-17 years (OR 3.22, 95% CI 1.62-6.41). Personally knowing someone who died by suicide was associated with suicidality outcomes for all age groups. We also assessed 2-year outcomes among respondents aged 12-15 years: a schoolmate's suicide predicted suicide attempts among participants aged 12-13 years (OR 3.07, 95% CI 1.05-8.96) and 14-15 years (OR 2.72, 95% CI 1.47-5.04). Among those who reported a schoolmate's suicide, personally knowing the decedent did not alter the risk of suicidality. Interpretation: We found that exposure to suicide predicts suicide ideation and attempts. Our results support school-wide interventions over current targeted interventions, particularly over strategies that target interventions toward children closest to the decedent.
Article
Full-text available
Since philosophers Beccaria and Bentham, criminologists have been concerned with predicting how governmental attempts to maintain lawful behavior affect subsequent rates of criminal violence. In this article, we build on prior research to argue that governmental responses to a specific form of criminal violence—terrorism—may produce both a positive deterrence effect (i.e., reducing future incidence of prohibited behavior) and a negative backlash effect (i.e., increasing future incidence of prohibited behavior). Deterrence-based models have long dominated both criminal justice and counterterrorist policies on responding to violence. The models maintain that an individual's prohibited behavior can be altered by the threat and imposition of punishment. Backlash models are more theoretically scattered but receive mixed support from several sources, which include research on counterterrorism; the criminology literature on labeling, legitimacy, and defiance; and the psychological literature on social power and decision making. In this article, we identify six major British strategies aimed at reducing political violence in Northern Ireland from 1969 to 1992 and then use a Cox proportional hazard model to estimate the impact of these interventions on the risk of new attacks. In general, we find the strongest support for backlash models. The only support for deterrence models was a military surge called Operation Motorman, which was followed by significant declines in the risk of new attacks. The results underscore the importance of considering the possibility that antiterrorist interventions might both increase and decrease subsequent violence.
Article
Full-text available
An important pursuit by a body of criminological research is its endeavor to determine whether interventions or policy changes effectively achieve their intended goals. Because theories predict that interventions could either improve or worsen outcomes, estimators designed to improve the accuracy of identifying program or policy effects are in demand. This article introduces the series hazard model as an alternative to interrupted time series when testing for the effects of an intervention on event-based outcomes. It compares the two approaches through an example that examines the effects of two interventions on aerial hijacking. While series hazard modeling may not be appropriate for all event-based time series data or every context, it is a robust alternative that allows for greater flexibility in many contexts. KeywordsHazard modeling–Time series–Event data–Series hazard model
Article
Full-text available
Previous work on publicized violence on television newcasts has been largely restricted to suicidal behavior. Many of the cases of publicized suicide, however, involve not only a suicide but a murder; they could also trigger homicides. In addition, from Menninger's perspective, suicide involves both a wish to die and a wish to kill. Hence, publicized mass murders may trigger imitiative suicides as well as imitative homicides. Focusing on mass murder-suicides, and mass murders that made two or three network news (ABC, CBS & NBC), the present study explores their impact on lethal aggression. It uses monthly data from 1968-1980. Controls are introduced for seasonal and economic predictors of aggression. Publicized mass murder/suicides are significantly associated with increases in the suicide rate. The homicide rate, in contrast, is not affected by publicized mass-murder/suicides. Publicized mass murders, in general, were unrelated to lethal aggression. One special type, publicized gangland mass murders, were, however, associated with increases in suicide.
Article
Many extensions of survival models based on the Cox proportional hazards approach have been proposed to handle clustered or multiple event data. Of particular note are five Cox-based models for recurrent event data: Andersen and Gill (AG); Wei, Lin and Weissfeld (WLW); Prentice, Williams and Peterson, total time (PWP-CP) and gap time (PWP-GT); and Lee, Wei and Amato (LWA). Some authors have compared these models by observing differences that arise from fitting the models to real and simulated data. However, no attempt has been made to systematically identify the components of the models that are appropriate for recurrent event data. We propose a systematic way of characterizing such Cox-based models using four key components: risk intervals; baseline hazard; risk set, and correlation adjustment. From the definitions of risk interval and risk set there are conceptually seven such Cox-based models that are permissible, five of which are those previously identified. The two new variant models are termed the ‘total time – restricted’ (TT-R) and ‘gap time – unrestricted’ (GT-UR) models. The aim of the paper is to determine which models are appropriate for recurrent event data using the key components. The models are fitted to simulated data sets and to a data set of childhood recurrent infectious diseases. The LWA model is not appropriate for recurrent event data because it allows a subject to be at risk several times for the same event. The WLW model overestimates treatment effect and is not recommended. We conclude that PWP-GT and TT-R are useful models for analysing recurrent event data, providing answers to slightly different research questions. Further, applying a robust variance to any of these models does not adequately account for within-subject correlation. Copyright © 2000 John Wiley & Sons, Ltd.
Article
Contents: Preface Introduction Part I ONE Murder as (Fine) Art TWO Murder as (Pure) Action THREE Murder as (Carnal) Knowledge Part II FOUR Mimesis and Murder FIVE Catharsis and Murder AFTERWORD Writing after Murder Notes Index
Article
In recent years, there have been numerous quasi-experimental studies of aggregate mortality data. These studies conclude that mass media portrayals of violence cause imitative responses among the public. This paper examines the logic of this research, arguing that it does not meet the special burdens of proof associated with quasi-experimental studies that use aggregate data to make inferences about individual behavior. We present detailed evidence suggesting that imitation effects attributed to mass media events (prize fights and television news stories about suicides) are statistical artifacts of the mortality data, the timing of media events, and the methods employed in past research. The concluding section discusses some implications of our analysis for future studies of imitative violence and for other areas of research.
Article
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.
Article
There are important controversies over the dynamics of terrorism which have not yet been formally addressed in quantitative social research. We suggest a class of stochastic models for social contagion which may help to shed light on these controversies. Empirical estimates of model parameters were obtained from data on international terrorism in 16 countries over 1968-78. We find some evidence suggesting that the tendency of acts of terrorism to incite further violence is more easily reversed in less democratic, poorer, and less well-educated societies. This suggests that reversal of a terrorism 'epidemic' is more likely under conditions facilitating repression rather than reform, and that more open societies face particular difficulties in responding to terrorism effectively.
Article
Statistical and graphic analyses of data from 40 U.S. cities indicate that President Kennedy's assassination in November 1963 and the Speck and Whitman crimes in the Summer of 1966 were followed by unusual increases in the number of violent crimes. Although we cannot exclude the possibility that only police actions (such as reporting violent crimes) were affected, the findings are suggestive of a contagion of criminal violence. Non-violent crimes did not appear to be affected. Some of the processe theoretically contributing to this kind of contagion aare discussed.
Article
The effect of exposure to media content containing criminal models is unresolved with two perspectives currently competing. One perspective perceives media provided models of crime functioning as direct causes of criminality or as crime triggers; the other sees media crime models serving as crime forming catalysts or as crime rudders. A study of copycat crime provided an opportunity to simultaneously weigh evidence for both models by examining the comparative roles of real world versus media provided crime models. Data obtained from the anonymous surveys of 574 male and female correctional inmates was employed. Results show that individual offenders, particularly young males, exposed to both real world and media crime model sources were at higher risk for copying criminal behaviors. While both real world and media sources contributed to predicting past inmate copycat behaviors, they also interacted significantly. With the additional enhancement of real world models, the media appear to form crime by providing instructional models to inclined individuals. The results did not support strong direct media exposure effects and the model of media as stylistic catalysts for crime was more supported. The media remains best perceived as a rudder for crime more than as a trigger.
Article
Between 1968 and 1972 there were 326 attempts to hijack aircraft worldwide, including 137 attempts in the United States. Those attempts were often attributed to imitation of previous hijacking incidents, and aircraft hijacking, like many other types of behavior, was described as a “contagious” phenomenon. In this article a general mathematical model is developed for serial dependence of rates at which events occur and is applied to data on the hijacking attempts in the U.S. during the 1968–1972 period.The general model leads to a class of autoregressive moving average (ARMA) time series models for Poisson-distributed variates. The ARMA parameters are constrained in such a way that clear interpretation of a process as either contagious or self-inhibiting is possible. The time series models can be generalized to distinguish effects of various subsets of prior incidents (e.g., previous successful and unsuccessful hijacking attempts) and to allow for effects of exogenous time series on the rate of occurrences. Procedures for maximum likelihood estimation and hypothesis testing are described in the Appendix.Unlike many other contagion models, ours is a model for a stationary stochastic process rather than for an epidemic. The underlying probability model is appropriate for aircraft hijacking data since it takes into account the rarity of hijackers in the U.S. population and the fact that the entire U.S. population was in contact with those “infected” individuals as a result of the nationwide publicity that hijacking attempts received. As a model for a stationary process, it takes into account the fact that aircraft hijacking neither began in 1968 nor ended in 1972.Parameter estimates for the models suggest that successful hijackings in the United States did indeed increase the subsequent rate of hijacking attempts during the 1968–1972 period; each successful hijacking generated about .5 new attempts, with a median delay of about 33 days. Unsuccessful attempts had neither a stimulating nor an inhibiting effect.
Article
Although the so-called “dark figure” crime measurement problem has never been a major concern for homicide researchers, the Supplementary Homicide Reports (SHR) as well as other local data series on murder still are plagued by other kinds of missing data issues. Most prominent is missingness in data pertaining to offender characteristics as well as to victim-offender relationship that results from uncleared cases. Ignoring unsolved homicides would, of course, seriously understate calculated rates of offending by particular subgroups of the population, would distort trends over time among these same subgroups, and would bias observed patterns of offending to the extent that the likelihood of missing offender data is associated with offender characteristics. This article presents several approaches for overcoming missing data problems in the 1976-2001 cumulative SHRdata file. First, a weighting procedure is described that uses characteristics of known offenders to serve as proxies for those of unidentified perpetrators. The weighting procedure included in the SHR file archived at ICPSR as well as an enhanced version are both presented and compared. Next, a “hot-deck” imputation strategy is applied to fill in missing offender attributes based on similar cases for which the offender is known. Finally, the matter of imputing victim-offender relationship data is discussed. Because this form of missingness cannot be assumed to occur at random, an ad-hoc procedure for estimating the number of intimate homicides among the pool of unsolved slayings is presented.
Article
This article is an introduction to the special issue of Homicide Studies on missing data. The first section is an overview of the status of missing data approaches in homicide research. It begins by describing the importance of missing data estimation in homicide. This is followed by a discussion of missing data mechanisms, complete case analysis, imputation and weighting, and model-based procedures. The second section is a brief description of each of the articles in this issue. The conclusion describes the myth associated with imputing missing data, the use of missing data approaches in public records, the Supreme Court case that found hot-deck imputation acceptable for the census, and guidelines for handling missing data published by the American Psychological Association. This section concludes by describing the kinds of research that need to be done.
Article
The impact of mass media violence on aggression has almost always been studied in the laboratory; this paper examines the effect of mass media violence in the real world. The paper presents the first systematic evidence indicating that a type of mass media violence triggers a brief, sharp increase in U.S. homicides. Immediately after heavyweight championship prize fights, 1973-1978, U.S. homicides increased by 12.46 percent. The increase is greatest after heavily publicized prize fights. The findings persist after one corrects for secular trends, seasonal, and other extraneous variables. Four alternative explanations for the findings are tested. The evidence suggests that heavyweight prize fights stimulate fatal, aggressive behavior in some Americans.
Chapter
Criminology can easily be characterized by its investigation of change. We need to understand the conditions that facilitate the change in order to inform policy makers on how to reduce crime or improve social welfare. Yet, much of the published research in our field relies on cross-sectional data. As most criminological research questions are inherently dynamic, criminologists have more recently adopted the methods of analyzing changes over time. This chapter introduces a set of methodological choices to estimate the effects of changes in an independent variable on a dependent variable. It begins by outlining several methodological options when the scholar has repeated the measures of a single unit. Then, several other options for a scenario in which the data include many units that are repeatedly measured, are discussed. The chapter concludes with a discussion designed to guide the readers’ methodological decisions while analyzing dynamic data.
Article
A series of seven mass-homicides occurring in Australia, New Zealand and the United Kingdom 1987--1996 is presented in the context of possible media influences. These crimes are exceptionally rare facilitating study based on similarity, time linkage and statements by the assailants. Time linkage suggests three incidents might have occurred through a modelling process. Statements link two incidents -- one not being linked by time. It is argued that modelling may have occurred over a period as long as ten years. A ripple effect with these incidents generating other serious violence may also have occurred. Researchers of media influences on suicide and homicide need to take into account the constraints on findings, in relation to time frames and ripple effects, imposed by macro research designs. The micro perspective afforded by the study of very rare massive publicity linked events may generate new insights. These findings raise ethical dilemmas for the media.
Article
The topic of media violence has been the subject of heated debate in recent decades. There is a vast empirical literature on the effects of television on aggression but no published comprehensive review has ever focused on those studies that use criminal aggression as their outcome. The present paper represents an attempt to fill this void and provide a resource for those who do not wish to delve into four decades of original research in order to assess this line of investigation. Studies are evaluated based on contemporary standards of research in the field of criminology. Although the possibility that television and film violence has an impact on violent criminality remains, it is concluded here that, despite persistent published reviews that state the contrary, the body of published, empirical evidence on this topic does not establish that viewing violent portrayals causes crime.
Conference Paper
Using data that combines information from the Federal Aviation Administration, the RAND Corporation and a newly developed database on global terrorist activity, we are able to examine trends in 1,101 attempted aerial hijackings that occurred around the world from 1931 to 2003. We have especially complete information for 828 hijackings that occurred before 1986. Using a rational choice theoretical framework, we use continuous-time survival analysis to estimate the impact of several major counterhijacking interventions on the hazard of differently motivated hijacking attempts and logistic regression analysis to model the predictors of successful hijackings. Some of these interventions use certainty-based strategies of target hardening to reduce the perceived likelihood of success. Others focus on raising the perceived costs of hijacking by increasing the severity of punishment. We also assess which strategies were most effective in deterring hijackers whose major purpose was related to terrorism. We found support for the conclusion that new hijacking attempts were less likely to be undertaken when the certainty of apprehension was increased through metal detectors and law enforcement at passenger checkpoints. We also found that fewer hijackers attempted to divert airliners to Cuba once that country made it a crime to hijack flights. Our results support the contagion view that hijacking rates significantly increase after a series of hijackings closely clustered in time—but only when these attempts were successful. Finally, we found that the policy interventions examined here significantly decreased the likelihood of nonterrorist but not that of terrorist hijackings.
Article
This analysis of the important components of the rising homicide rates, the changing patterns in means of injury, and the relative increase in the number of victims at older ages indicates that unless present violent behavior is drastically altered, no downturn in the victim rate may be expected until the 1980s.
Article
Many extensions of survival models based on the Cox proportional hazards approach have been proposed to handle clustered or multiple event data. Of particular note are five Cox-based models for recurrent event data: Andersen and Gill (AG); Wei, Lin and Weissfeld (WLW); Prentice, Williams and Peterson, total time (PWP-CP) and gap time (PWP-GT); and Lee, Wei and Amato (LWA). Some authors have compared these models by observing differences that arise from fitting the models to real and simulated data. However, no attempt has been made to systematically identify the components of the models that are appropriate for recurrent event data. We propose a systematic way of characterizing such Cox-based models using four key components: risk intervals; baseline hazard; risk set, and correlation adjustment. From the definitions of risk interval and risk set there are conceptually seven such Cox-based models that are permissible, five of which are those previously identified. The two new variant models are termed the 'total time - restricted' (TT-R) and 'gap time - unrestricted' (GT-UR) models. The aim of the paper is to determine which models are appropriate for recurrent event data using the key components. The models are fitted to simulated data sets and to a data set of childhood recurrent infectious diseases. The LWA model is not appropriate for recurrent event data because it allows a subject to be at risk several times for the same event. The WLW model overestimates treatment effect and is not recommended. We conclude that PWP-GT and TT-R are useful models for analysing recurrent event data, providing answers to slightly different research questions. Further, applying a robust variance to any of these models does not adequately account for within-subject correlation.
Article
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.
The contagion of criminal violence The Aesthetics of Murder. A study in romantic literature and contemporary culture
  • L Macaulay
  • J Black
  • Ch Cantor
  • Alpers P P Sheehan
  • Mullen
L, Macaulay J (1971) The contagion of criminal violence. Sociometry 34:238–260 Black, J. (1991). The Aesthetics of Murder. A study in romantic literature and contemporary culture. The Johns Hopkins University Press. Cantor CH, Sheehan P, Alpers P, Mullen P (1999) Media and Mass Homicides. Arch Sui Res 5:283–290
The mass murder as quasi-experiment
  • C Carcas
  • J Mouzos
  • P Grabosky
C, Mouzos J, Grabosky P (2002) The mass murder as quasi-experiment. Hom Stud 6:109–127
Introduction to Mathematical Sociology Homicide trends in the United States
  • Coleman
  • A Cooper
  • E L Smith
Coleman JS (1964) Introduction to Mathematical Sociology. Free Press, New York Cooper, A. and Smith E.L. (2011). Homicide trends in the United States 1980-2008: Annual Rates for 2009 and 2010. United States Department of Justice, Bureau of Justice Statistics Dietz PE (1986) Mass, Serial, and Sensational Homicides. Bul New York Acad Med 62:477–491
Criminal Behavior: Theories, Typologies, and Criminal Justice The contagiousness of aircraft hijacking Time series analysis of a contagious process Shooting for accuracy: Comparing data sources on mass murder
  • J B Huff-Corzine
  • L Mccutcheon
  • J C Corzine
  • J P Jarvis
  • M J Tetzlaff-Berniller
  • M Weller
  • M London
, J.B. (2008). Criminal Behavior: Theories, Typologies, and Criminal Justice. Sage Publications, Inc. Holden RT (1986) The contagiousness of aircraft hijacking. Am J Soc 91: 874–904 Holden RT (1987) Time series analysis of a contagious process. J Am Stat Assoc 82:1019–1026 Huff-Corzine, L., McCutcheon, J.C., Corzine, Jarvis, J.P., Tetzlaff-Berniller, M.J., Weller, M. and London, M. (2014). Shooting for accuracy: Comparing data sources on mass murder. Hom. Stud. 18: 105–124.
Active Shooter: Recommendations and analysis for risk mitigation New York City Police Department Survival analysis for recurrent event data: An application to childhood infectious diseases
  • R W Kelly
  • Pj Kelly
  • Lim
  • Ly
Kelly, R.W. (2012). Active Shooter: Recommendations and analysis for risk mitigation. New York City Police Department. Kelly PJ, Lim LY (2000) Survival analysis for recurrent event data: An application to childhood infectious diseases. Stat Med 19:13–33
Imation[sic] of amok and amok-suicide
  • A Schmidtke
  • S Schaller
  • L Miller
A, Schaller S, Miller L (2002) Imation[sic] of amok and amok-suicide. Kritz Dergisi 10:49–60
Active Shooter: Recommendations and analysis for risk mitigation
  • R W Kelly
Testing a rational choice model of airline hijackings
  • L Dugan
  • G Lafree
  • Ar Piquero
What mass killers want-and how to stop them
  • A N Schulman
Criminal Behavior: Theories, Typologies, and Criminal Justice
  • J B Helfgott
Shooting for accuracy: Comparing data sources on mass murder
  • L Huff-Corzine
  • J C Mccutcheon
  • Corzine
  • J P Jarvis
  • M J Tetzlaff-Berniller
  • M Weller
  • M London
Homicide trends in the United States 1980-2008: Annual Rates for
  • A Cooper
  • E L Smith