Urban Wire Three Evidence Gaps We Need to Fill to Better Support Survivors of Mass Violence and Terrorism
Emily Tiry, Mel Langness
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Flowers outside the Tree of Life Synagogue

By some measures, 2020 has had the most mass shootings of any recent year, despite the coronavirus pandemic shutting down many workplaces, schools, and public venues. And mass violence events are continuing to happen. Mass violence events are traumatic for and have lasting effects (PDF) on survivors and communities. They are challenging to recover from, and current evidence gaps make it more difficult to effectively respond to these events and support survivors’ recovery.

We have been exploring and elevating the needs of mass violence survivors and their communities through our work with the Center for Victim Research (CVR). Funded by the Office for Victims of Crime, CVR is a joint effort by the Justice Research and Statistics Association, the Urban Institute, and the National Center for Victims of Crime. CVR aims to foster collaboration between victim service providers and researchers and to improve practice through effective use of research and data.

CVR recently released the first-ever synthesis (PDF) of research- and practice-based evidence on mass violence and terrorism (MVT) victimization in the United States. The resource highlights three major gaps in the evidence that, if filled, could strengthen policies and practices that support MVT survivors and more effectively address their needs.

1. We don’t know how many people are harmed by MVT events in the US

There is no single definition of a mass violence event, which makes it difficult to quantify how many occur annually. Most data sources that define and track these types of events focus on mass shootings, leaving out other types of mass violence events (such as intentional vehicle attacks and attacks using explosives).

Many existing data sources also define victims as people who were physically injured or killed in the attack, which excludes people who are harmed in less visible ways—such as those who experience psychological harm, families of people who are injured or killed, and members of communities where traumatic events occurred. On average, about 30 percent of people who experience a mass casualty event develop a significant psychiatric disorder, such as posttraumatic stress disorder, depression, or substance use disorder. Others may experience prolonged grief if they lost a loved one during the event, which can complicate recovery for them and their families—similar to the effects on people who lose loved ones to other types of homicide.

Without knowing the true extent of MVT victimization, it is challenging for communities and governmental agencies to adequately support everyone harmed by an MVT event.   

2. MVT victimization is difficult to predict

Little to none of the existing evidence has identified individual characteristics that put people at risk of mass violence and terrorism. Often, MVT survivors are in the wrong place at the wrong time.

Instead, evidence focuses on how certain policies can place communities at higher risk of an MVT event. Research shows that areas with higher levels of income inequality and increasing income inequality are more likely to experience mass shootings. Other research demonstrates that areas with more permissive gun laws and higher levels of gun ownership tend to have more mass shootings.

Some recent policy recommendations to address causes of MVT events include changing media coverage of public mass shooters, limiting access to firearms, improving threat detection systems, and formally tracking and researching mass violence at the federal level. But without a better understanding of the reasons behind these events, policymakers and practitioners won’t be able to target resources and services to prevent them or mitigate their harms.

3. Most existing MVT victimization research does not acknowledge structural racism’s role in how we research and respond to MVT events

Evidence on MVT victimization shows that structural racism in the US has influenced mass violence research and response in several ways. In particular, it influences which events are considered MVT events and, therefore, which types of events and survivors receive MVT response resources.

Racist stereotypes of Black and low-income communities as “violent” have perpetuated the belief that mass violence in these communities is expected and, as such, has been largely ignored in mass violence research. For example, efforts to document mass violence often exclude events related to gangs, drugs, or other criminal activity, even though community effects of these types of events may be similar.

Mass violence can be psychologically damaging for entire communities, even for people not directly affected. This is particularly true for Black communities facing mass trauma from gun violence and the threat of police brutality, as well as other marginalized communities who may be targeted based on racist stereotypes and belief systems. Further, despite a significant pattern linking mass violence and terrorism events to white supremacist and white nationalist groups, authorities have been reluctant to recognize these types of events as terrorism.

Identifying and naming the root causes of mass violence while working to better understand its prevalence could reduce inequity in the level of resources available to support survivors.

Addressing evidence gaps in MVT research, policy, and practice can help support survivors

Although the evidence base on mass violence and terrorism victimization is growing, it still contains gaps that prevent survivors from obtaining the services they need, and these gaps constrain policymakers from implementing effective policies to prevent these events and mitigate their harm. Expanding common definitions of MVT victims and centering their experiences could make future research, policy, and practice more effective and inclusive.

Research Areas Crime, justice, and safety
Tags Victims of crime Crime and justice analytics
Policy Centers Justice Policy Center