By The Sandy Hook Advisory Commission

On December 14, 2012, one of the most vicious and incomprehensible domestic attacks in American history occurred at Sandy Hook Elementary School in Newtown, Connecticut. Within a few hours, the world understood the gravity of the attack. Lives were lost in two distinct locations: Sandy Hook Elementary School and a private residence in Newtown. The scope of the tragedy would take on international proportions, and people from around the world would grieve and mourn alongside the families of Newtown.

Hartford, CT: Sandy Hook Advisory Commission, 2015) 277p.

By Jason R. Silva and Emily A. Greene-Colozzi

This research brief will explore what we know about foiled and failed mass school shootings—referring to incidents and plots that resulted in zero victim casualties. Findings will illustrate the common mass school shooting perpetrator and incident characteristics, as well as what contributed to these attacks being thwarted. Actionable takeaways based on the research will illustrate future strategies for prevention and intervention including leakage and warning signs, as well as situational crime prevention.

Albany, NY: Rockefeller Institute of Government, 2022. 24p.

By Columbine Review Commission

The Commission conducted 15 meetings open to members of the public. The Commission received statements from an extensive list of State and local officials and private persons who had experience with or information concerning the event; Commission staff reviewed thousands of pages of official and unofficial documents, reports, and studies. Two recommendations related to crisis response actions. First, law enforcement policy and training should emphasize that the highest priority of law enforcement officers, after arriving at the scene of a crisis, is to stop any ongoing assault. Second, there should be an increased emphasis on training appropriate personnel in preparation for and responding to large-scale emergencies. Two recommendations pertained to improved communications for critical emergencies. First, law enforcement agencies should plan their communications systems to facilitate crisis communication with other agencies with whom they might reasonably be expected to interface in emergencies. Second, Colorado should continue to develop a single statewide digital trunked communications system. Other categories of recommendations pertained to advance planning for critical emergencies; interaction with media representatives; tasks of school resource officers; detection by school administrators of potential perpetrators of school-based violence and administrative countermeasures; medical treatment for attack victims; reuniting attack victims and their families; identification of victims' bodies and family access to bodies; and suicide prevention in the aftermath of traumatic incidents.

Denver, Colo. : Columbine Review Commission, 2001. 174p.

By The Office of the Child Advocate

In January, 2013, the Office of the Child Advocate was directed by the Connecticut Child Fatality Review Panel to prepare a report that would focus on Adam Lanza (hereinafter referred to as AL), and include a review of the circumstances that pre-dated his commission of mass murder at Sandy Hook Elementary School. The charge was to develop any recommendations for public health system improvement that emanated from the review. Authors of this report focused on AL’s developmental, educational, and mental health profile over time, the services he received from various community providers, and ultimately his condition prior to his actions on December 14, 2012. Authors looked for any warning signs, red flags, or other lessons that could be learned from a review of AL’s life. It was not the primary purpose of this investigation to explicitly examine the role of guns in the Sandy Hook shootings. However, the conclusion cannot be avoided that access to guns is relevant to an examination of ways to improve the public health. Access to assault weapons with high capacity magazines did play a major role in this and other mass shootings in recent history. Our emphasis on AL’s developmental trajectory and issues of mental illness should not be understood to mean that these issues were considered more important than access to these weapons or that we do not consider such access to be a critical public health issue.

Hartford, CT : State of Connecticut, Office of the Child Advocate, 2014. 114p.

By William S. Pollack, William.; Modzeleski, and Rooney, Georgeann

In the wake of several high-profile shootings at schools in the United States, most notably the shootings that occurred at Columbine High School on April 20, 1999, the United States Secret Service (Secret Service) and the United States Department of Education (ED) embarked on a collaborative endeavor to study incidents of planned (or "targeted") violence in the nation's schools. Initiated in 1999, the study, termed the Safe School Initiative (SSI), examined several issues, most notably whether past school-based attacks were planned, and what could be done to prevent future attacks. The SSI findings highlight that in most targeted school-based attacks, individuals, referred to as "bystanders" in this report, had some type of advanced knowledge about planned school violence. Despite this advanced knowledge, the attacks still occurred. This study aimed to further the prevention of targeted school-based attacks by exploring how students with prior knowledge of attacks made decisions regarding what steps, if any, to take after learning the information. The study sought to identify what might be done to encourage more students to share information they learn about potential targeted school-based violence with one or more adults. Six key findings were identified. Given the small sample size and the exploratory nature of the study, generalization from these findings may be limited. The findings are: (1) The relationships between the bystanders and the attackers, as well as when and how the bystanders came upon information about the planned attacks, varied; (2) Bystanders shared information related to a threat along a continuum that ranged from bystanders who took no action to those who actively conveyed the information; (3) School climate affected whether bystanders came forward with information related to the threats; (4) Some bystanders disbelieved that the attacks would occur and thus did not report them; (5) Bystanders often misjudged the likelihood and immediacy of the planned attack; and (6) In some situations, parents and parental figures influenced whether the bystander reported the information related to the potential attack to school staff or other adults in positions of authority,

Washington, DC: United States Secret Service and United States Department of Education, 2008. 15p.

By Jaclyn Schildkraut

The first five months of 2021 saw high-profile public mass shootings in cities across the United States of America, like Atlanta, Georgia (March 16, 8 dead), Boulder, Colorado (March 22, 10 dead), Indianapolis, Indiana (April 15, 8 dead), and San Jose, California (May 26, 9 dead). Following a year where such events rarely made headlines as the nation found itself in the throes of the coronavirus pandemic, these incidents revived the public discourse about mass shootings in America, as well as how to prevent and respond to such tragedies. This dialogue raised an important question: As society returns to normal after the COVID-19 pandemic, what does the future of mass shootings look like? To answer this, it is important to understand the trends associated with the phenomenon of mass shootings. The first issuance of this policy brief in 2018 examined 51 years (1966-2016) of mass shootings data based on a comprehensive database from researchers Jaclyn Schildkraut and H. Jaymi Elsass.3 As described below, the researchers developed their own definition that became the foundation of this analysis given deficiencies with existing classifications and data sources. This updated brief provides analyses including an additional four new years of data since the original 2018 policy brief to identify changes in trends and broader considerations for policymakers, particularly given the COVID-19 pandemic’s impact and lessons learned from specific shootings within this period. Specifically, this brief presents and analyzes a total of 55 years of mass shooting data from 1966 to 2020, including frequency, injury and fatality, location type, weapon usage, and perpetrator demographics. The appendix contains information on only the most recent four years of data from 2017 to 2020.

Albany, NY: Rockefeller Institute of Government, 2021. 25p.

By Michael Rocque, Grant Duwe, Michael Siegel, James Alan Fox, Max Goder-Reiser, and Emma E. Fridel

In the past decade, mass shootings, particularly those that take place in public areas, have increasingly become part of the national conversation in the United States. Mass public shootings instill widespread fear, in part because of their seeming randomness and unpredictability. Yet when these incidents occur, which has been with somewhat greater frequency and lethality as of late, public calls for policy responses are immediate. In this policy brief, we review efforts to evaluate the effect of gun control measures on mass public shootings, including a discussion of our recently published study on the relationship between state gun laws and the incidence and severity of these shootings. The findings of this work point to gun permits and bans on large capacity magazines as having promise in reducing (a) mass public shooting rates and (b) mass public shooting victimization, respectively. Interestingly, however, most gun laws that we examined, including assault weapon bans, do not appear to be causally related to the rate of mass public shootings.

Albany, NY: Rockefeller Institute of Government, 2021. 20p.

By J,M, Nowicki

GAO found that shootings at K-12 schools most commonly resulted from disputes or grievances, for example, between students or staff, or between gangs, although the specific characteristics of school shootings over the past 10 years varied widely, according to GAO’s analysis of the Naval Postgraduate School’s K-12 School Shooting Database. (See figure.) After disputes and grievances, accidental shootings were most common, followed closely by school-targeted shootings, such as those in Parkland, Florida and Santa Fe, Texas.

Washington, DC: Government Accountability Office, 2020. 58p.

By Jay Van Kirk

Mass shootings occur on a regular basis in the United States, and depending on the definitions applied to the shootings an argument can be made that mass shootings of all types occur far more often than what is reported in the media as a “mass shooting.” Unfortunately, school shootings are also part of this analysis of mass shootings, and school shootings in the United States have occurred on a recurring basis since at least 1853. In the modern era, however, school shootings have become more frequent and more deadly as demonstrated by the May 24th, 2022, school shooting in Uvalde, Texas. This heinous crime at Robb Elementary School resulted in the deaths of nineteen children, and two teachers. Although there has been extensive research on mass shooters, mass shootings, and mass shootings in schools, there has not been enough emphasis on the application of homeland javascript:void(0);security principles of target hardening in schools as a risk mitigation factor for mass shootings. In fact, there is much that can be done to keep schools safe through basic target hardening measures, and many of these security updates can be immediately undertaken at the state and local level with relatively minor additional cost to schools and the taxpaying public. This paper references the mass shooting on February 14, 2018, at Marjory Stoneman Douglas High School in Parkland, Florida, and makes policy recommendations toward basic target hardening measures which may be applied as necessary within the public school K-12 environment. The school shooting at Marjory Stoneman Douglas High School was selected due to the fact that it has been recently investigated regarding the facts and circumstances of the incident, and provides ample information for analysis of effective target hardening measures.

Des Moines, IA: Des Moines Area Community College, 2022. 17p.

By William Krouse and Daniel J. Richardson

In the wake of tragedy in Newtown CT, Congress defined “mass killings” as “3 or more killings in a single incident” (P.L. 112-265). Any consideration of new or existing gun laws that follows mass shootings is likely to generate requests for comprehensive data on the prevalence and deadliness of these incidents. Despite the pathos of mass shootings, only a handful of researchers and journalists have analyzed the principal source of homicide data in the United States—the Supplementary Homicide Reports (SHR) compiled by the Federal Bureau of Investigation (FBI)—to determine whether those incidents have become more prevalent and deadly. According to the FBI, the term “mass murder” has been defined generally as a multiple homicide incident in which four or more victims are murdered, within one event, and in one or more locations in close geographical proximity. Based on this definition, for the purposes of this report, “mass shooting” is defined as a multiple homicide incident in which four or more victims are murdered with firearms, within one event, and in one or more locations in close proximity. Similarly, a “mass public shooting” is defined to mean a multiple homicide incident in which four or more victims are murdered with firearms, within one event, in at least one or more public locations, such as, a workplace, school, restaurant, house of worship, neighborhood, or other public setting. This report analyzes mass shootings for a 15-year period (1999-2013). CRS analysis of the FBI SHR dataset and other research indicates that offenders committed at least 317 mass shootings, murdered 1,554 victims, and nonfatally wounded another 441 victims entirely with firearms during that 15-year period. The prevalence of mass shooting incidents and victim counts fluctuated sporadically from year to year. For the period 2007-2013, the annual averages for both incidents and victim counts were slightly higher than the years from 1999-2007.

Washington, DC: Congressional Research Service, 2015. 51p.

By Michael Luca, Deepak Malhotra. and Christopher Poliquin

There have been dozens of high-profile mass shootings in recent decades. This paper presents three main findings about the impact of mass shootings on gun policy. First, mass shootings evoke large policy responses. A single mass shooting leads to a 15% increase in the number of firearm bills introduced within a state in the year after a mass shooting. This effect increases with the extent of media coverage. Second, mass shootings account for a small portion of all gun deaths, but have an outsized influence relative to other homicides. Third, when looking at bills that were actually enacted into law, the impact of mass shootings depends on the party in power. The annual number of laws that loosen gun restrictions doubles in the year following a mass shooting in states with Republicancontrolled legislatures. We find no significant effect of mass shootings on laws enacted when there is a Democrat-controlled legislature, nor do we find a significant effect of mass shootings on the enactment of laws that tighten gun restrictions.

Boston, MA: Harvard Business School, 2019. 59p.

By Ralph Larkin. 

On April 20, 1999, two Colorado teenagers went on a shooting rampage at Columbine High School. That day, Eric Harris and Dylan Klebold killed twelve fellow students and a teacher, as well as wounding twenty-four other people, before they killed themselves. Although there have been other books written about the tragedy, this is the first serious, impartial investigation into the cultural, environmental, and psychological causes of the massacre. Based on first-hand interviews and a thorough reading of the relevant literature, Ralph Larkin examines the numerous factors that led the two young men to plan and carry out their deed. Rather than simply looking at Columbine as a crucible for all school violence, Larkin places the tragedy in its proper context, and in doing so, examines its causes and meaning.

Philadelphia: Temple University Press, 2007. 265p.

By Steffen Hurka.

Politicization and Policy Change in Western Europe. While the causes of rampage violence have been analysed thoroughly in diverse academic disciplines, we hardly know anything about the factors that affect their consequences for public policy. This book addresses rampage shootings in Western Europe and their conditional impact on politicization and policy change in the area of gun control. The author sets out to unravel the factors that facilitate or impede the access of gun control to the political agenda in the wake of rampage shootings and analyses why some political debates lead to profound shifts of the policy status quo, while others peter out without any legislative reactions. In so doing, the book not only contributes to the theoretical literature on crisis-induced policy making, but also provides a wealth of case-study evidence on rampage shootings as empirical phenomena.

London; New York: Routledge, 2017. 201p.