Mass Shootings: Data-Driven Strategies for Prevention | Interview with Criminologists Peterson & Densley

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Article Authors: Brice Thomas, BA, Jonathan Nowlin, MA, David Puder, MD

Introduction

Mass shootings are a constant fear in American culture today. A 2019 poll reported that one-third of adults say they feel they “cannot go anywhere without worrying about being a victim of mass shooting” and “more than half of American teenagers worry about a shooting at their school.” While there are a variety of definitions, a mass shooting is generally defined as the murder of at least four people at one time. Why do mass shootings take place? Are there any commonalities between the perpetrators? Could these shootings have been stopped before they started? Are there any warning signs? What can we do to prevent such atrocities from happening?

In this episode, we speak with Jillian Peterson, PhD, and James Densley, PhD, who are professors of criminology. They have spent several years creating https://www.theviolenceproject.org/, which is the largest database on mass shooters. Throughout this article, we will include tables with data from the database, presenting the raw numbers and percentages. We hope this will give sobering insights into the complex nature of mass shootings.

Today they launch their new book, The Violence Project: How to Stop a Mass Shooting Epidemic. Drs. Peterson and Densley share their expertise on mass shooters through their exhaustive research (including interviews with perpetrators) to give us an inside look into the common characteristics and intentions of mass shooters. This will help us better understand mass shooters so that we can work as a society to prevent future mass shootings.

Dr. Peterson, Dr. Densley, and Dr. Puder don’t have any conflicts of interest to report.

Media Portrayal

“We worship that which we fear.”

Therefore, we should teach the public to fear the heroes…

One of the biggest issues with mass shootings is the massive amount of media coverage each occurrence receives. When it comes to mass shooters, there is an intense fear and fascination from the public at large. Similar to why documentaries featuring Ted Bundy, Zodiac, BTK Killer, and numerous other serial killers are immensely popular, mass shooters often achieve unnerving notoriety. As we will learn, mass shooters do not perfectly align with the profile of these serial killers, but the publicity remains similar for both.

One problem with the heavy publicity of mass shootings is that potential perpetrators may use previous mass shootings as blueprints for “success.” They see what can be achieved and follow suit. Coverage via news outlets and social media sites can be a dangerous contributing factor, because it suggests to struggling individuals that committing such an atrocity is an option. To prevent the unintentional encouragement of potential mass shooters, we must starve the oxygen of publicity from these events.

The issue starts with an intense desire for fame and publicity that is embedded in American culture. When potential mass shooters are struggling with isolation from society, they see an opportunity to be heard and remembered through immortalization by the media. Here are several ways to prevent further publicity:

Treat media coverage on mass shootings in the same manner as suicides. Reporting suicides does not focus on the detail of the event but rather the grief of the family and how to get help if one has thoughts of suicide.
Stop sharing the names and images of the perpetrators.
Talk about how to support families and communities who are grieving rather than focusing on the means and methods of the mass shooting.
Provide a way for possible copycats to connect with organizations who can help them deal with their issues in a positive manner (suicide reporting always has a suicide hotline number given).
Shift the attention to the survivors and true heroes of the situation rather than giving the perpetrator a stage due to their violent actions. Say the heroes' names and tell their stories.
Shift our unhealthy fascination from the perpetrators to the heroes by being intentional about who we are celebrating and remembering.

Another negative effect of publicizing mass shootings is that people fear greater restrictions on guns, which often leads to more gun sales. Although there are a few instances of armed civilians stopping potential mass shooters, it is well known that more guns lead to more access to people at risk of perpetrating mass shooting events. Both political parties should embrace common-sense gun safety laws, which include locking up guns at all times and comprehensive policies to stop people in crisis from accessing guns. Data on guns are reported at the end of this article for those interested in what types of guns are used in mass shootings.

Secondly, reactive and fear-based approaches that come after the mass shootings have not been helpful. There is a multi-billion-dollar industry around school safety, school security, and workplace violence prevention, which is all focused on reaction. This contributes to greater fear and makes the threat more real. Making policy decisions based solely on fear does not create lasting public policy. We must better understand the life history and characteristics of mass shooters to find durable and preventive policy measures.

Victim, Perpetrator, or Both?

“I didn’t meet any monsters. I met humans who had done monstrous things, but they were still humans.”

As we try to grasp the horrific events that occur in the world, it is human nature to categorize people as the victim or the villain, an age-old dichotomy. We want to put these stories into well-demarcated boxes that are easy-to-understand. However, to prevent further mass shootings, we must gain a more complex and nuanced understanding of the individuals who commit these atrocities, because “the worse the crime the worse the story.” Some feel that when we begin to humanize these individuals, we minimize their horrible actions, hurt the victims, or absolve the perpetrator of responsibility. But in trying to understand the complex human stories that lead up to these tragedies, we do not detract from the horrific nature of their actions or absolve them from the punishment they deserve. Better understanding these shooters does not dilute the pain felt by families and victims. In fact, in better understanding the human beings behind these horrific events, we come closer to creating preventative measures.

Using labels for mass shooters such as “madmen” or “monsters” does not explain the motivation for this phenomenon. These labels do not help stop future mass shootings and may even prevent preventive measures. This is because using these terms effectively places the shooters in the “crazy” box, which allows us to move on rather than getting to the root of the issue. Arguments against mass shooters often point to either gun control issues or mental health instability, but the data presented here reveals a wide range of potential causes for these events. Only through a more comprehensive and nuanced understanding can we prevent mass shootings.

Trauma

School systems have multiple barriers in the prevention of mass shootings. First, there are simply not enough counselors, mental health professionals, and community resources. The bureaucracy in public schools can be overwhelming for counselors who are trying to help the student body. Counselors have told me that they often spend the vast majority of their time filling out paperwork rather than helping students. Teachers' kindness and relationships with students likely prevents many suicides and homicides, and many teachers become lay therapists due to the close connections with students. However, teachers also face obstacles in helping students, including large class sizes.

Given that the database reveals many psychosocial factors preceding mass shootings, we can better understand how teachers, school counselors and mental health professionals are key in helping to prevent these events. However, these professionals need more support to fulfill their important roles and prevent mass shootings.

Table displaying trauma factors among mass shooters, including bullying, single parent upbringing, parental suicide, childhood trauma, socioeconomic status, and adult trauma. Data shows percentages of shooters affected by these factors. — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Crisis

“Too often we’ve said ‘unless the legislator does something then we can only do nothing.”

The database reveals that 84% of mass shooters were in crisis in the days or weeks leading up to the shooting. A crisis is considered a marked change in baseline behavior that puts them at risk of hurting themselves or others and/or prevents them from being able to function. An unfortunate commonality with many school shootings is that faculty and students were not shocked to discover who the perpetrator was. Most of the time, the perpetrator had been on people’s radar due to previous threats. Many were known to be depressed or suicidal, and many had a history of being excluded within the school and greater community. This means that while people close to potential shooters often have concerns about them, these students did not receive the interventions they needed. This is because faculty and students often do not know what to do, which can lead to exclusionary and severe interventions like criminal charges, suspension, and expulsion. However, these actions do not address the underlying problem and often serve to heighten students’ disdain towards the school and their community.

Table showing crisis factors among mass shooters, including recent breakups, work issues, signs of crisis, ongoing stressors, inability to perform daily tasks, mood changes, isolation, abusive behavior, and losing touch with reality. — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Some teachers report having a “teacher gut,” which senses kids in crisis. But many feel uncomfortable reporting their instincts, thinking that the reporting of students in crisis will result in punitive action rather than more beneficial supportive interventions. In addition, many peers of mass shooters are aware of problems, but they also fail to report their concerns due to fears of being labeled a ‘snitch.’ Finally, parents in these communities too often ignore signs of crisis or downplay concerning behavior by attributing them to a kid’s personality. In each of these scenarios, people in a position to report concerning behavior choose not to, which results in the person in crisis not getting the help they need. Unfortunately, this propagates the cycle of violence.

Another major structural barrier to preventive care for perpetrators is the reliance of healthcare on employment. Many insurance plans are received through employers, which means that one is out of luck without employment. The pandemic, in particular, has revealed holes in this system since many people have been unable to work. Because the healthcare system is too expensive for ordinary people to afford insurance, many have great difficulty accessing the care they need. This is a structural barrier to preventive care in many areas of healthcare, including mass shootings.

Is it linked to psychopathy?

“Mass Shootings are suicides. But, they’re suicides meant to make headlines.”

Surprisingly, the vast majority of mass shooters do not align with the qualities outlined by the psychopathy checklist. There exist some links with the factor two signals (e.g., impulsivity), but most factor one personality indicators (e.g., callousness, manipulation, or emotional flatness) do not fit the profile of mass shooters.

Below are data of the mental health characteristics of mass shooters.

Table displaying health and mental health factors among mass shooters, including suicidality, psychiatric hospitalization, prior counseling, prescribed medications, psychosis, autism spectrum disorder, and substance use.

The presence of suicidality represents a major division between mass shooters and those who exhibit psychopathy. Most mass shooters plan to die in the act either by killing themselves or being killed by the police. It is a different mentality entering a crime with the expectation that it is one’s final action. Surprisingly, this makes mass shootings more akin to an act of suicide rather than homicide. This represents an important shift that we must make as a society, because it will determine how we choose effective deterrents and preventive measures.

Is it linked to medications?

In the 2022 update of the Mass Shooter Database, out of 182 cases of mass shooters, there were only 34 with known mental health treatment in the past 6 months. Out of the 182 there were only 43 that had ever been prescribed psychiatric medications (the rest had no evidence of being on a psychiatric medication).

Here is a list of the people who were on a psych medications at some point in their life (it was unclear from the database at what point they were on it in their past):

#9 unspecified sleep aid

#21 Thorazine

#36 unspecified depression medication

#37 unspecified

#38 Prozac

#59 Haldol, Cogentin

#66 unspecified anxiety/depression/OCD medications

#66 medications

#69 Prozac

#70 Elavil, Trazodone

#72 Luvox

#73 Ritalin

#79 19 unspecified medications

#80 Prozac, Trazodone

#83 Unspecified

#87 Unspecified

#92 Unspecified

#95 Prozac

#102 Paroxetine, Ativan

#103 Ritalin, Zoloft, Mellaril, Pamelor, Effexor XR

#104 Prozac

#106 Prozac, Zyprexa, Depakote, Paxil, Cogentin, Risperdal, Lithium, Cylert, Seroquil, Clozaril, Xanax

#107 Unspecified

#109 Unspecified

#110 Lexapro, Xanax, Ambien

#122 Unspecified

# 123 Unspecified

#126 Zoloft

#128 Trazodone, Mirtazapine, Temazepam, Wellbutrin

#134 Trazodone

#136 unspecified

#138 Xanax, Prozac, Paxil

#139 unspecified

#140 unspecified

#141 unspecified

#148 unspecified

#149 Prozac, Guanfacine, Concerta

#154 Valium

#155 Clonazepam, Celexa, Ambien, Atomexitine, Strattera, Wellbutrin

#158 Clonidine, Focalin, Risperidone

#170 Xanax

#171 unspecified

#179 Lexapro, Intuniv

#180 unspecified

As you can see, most of the mass shooting did not have psychiatric medication as a treatment and most did not receive mental health services in the 6 months prior to the event.

Changes in Modern Times

Last-stand suicidal mass shootings are prevalent in America, because perpetrators have access to guns and the media provides a final platform. Interestingly, homicides in the United States have decreased in the last 40 years, while mass shootings have increased. This begs the question: what is causing the rise in mass shootings? Early childhood trauma and major life stressors have been common throughout human history, but what has changed in today’s society is the prevalence of media and social media. This has created polarized debates that incite us to anger against particular groups and may lead to devastating actions. Media outlets also provide a platform to repeatedly tell the stories of mass shooters.

Easy access to firearms is another development in the modern age, which gives perpetrators the ability to carry out mass shootings. Even children are able to access guns, because gun safety protocols are not always followed. In fact, 80% of school shooters gained access to firearms from their parents or grandparents because the weapons had not been locked up properly. (If your weapons are not locked up and you are reading this, stop and go lock them up right now.) While this represents an opportunity for better laws and policies, every gun owner can affect change now by practicing gun safety. As a society, we must choose to secure weapons to prevent kids from accessing them. This is a common sense preventive action that can be done immediately. Please share this information.

Table showing data on mass shooters' interest in firearms, firearm proficiency levels, and use of other weapons. It includes percentages of shooters with varying firearm experience and notable interest in firearms. — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

What is the racial break down of Mass Shooters?

The table below shows the overall percentage of mass shooters, but different races tend to show up in certain settings more often. In the audio interview, Dr. Peterson commented the following:
- High school shooters are disproportionately white (84.6%)
- University shooters are disproportionately Asian (44.4%)
- Workplace shooters are disproportionately black (29.1%)

Table displaying the background of mass shooters, including gender, race, immigrant status, sexual orientation, religion, education, school performance, relationship status, parenthood, employment, military service, and community involvement.

Myths Debunked

There are several myths surrounding mass shooters, largely due to media coverage that presents statistics in a biased manner. Here we present data from the Mass Shooter Database, which provides a more complete picture into mass shootings and debunks many of these commonly-reported myths.

Myth: The motivation is the same every time

Some shooters’ crimes are motivated by racism and hatred, which lead to targeted shootings.
- White supremacists are largely responsible for racially-motivated shootings (12 out of 176 known cases).
- Some churches are targeted based on hatred.
Some shooters have experienced racism themselves, which may contribute to the preceding crisis in their life.
- It motivates them to take revenge (more common in the workplace).
- The workplace can be a symbol of unmet goals and frustrations, which can be interpreted through race.
- Both the real and perceived view of racism in the workplace can lead to disgruntled employees in crisis who choose to take out their anger in the workplace.
Mass shootings are nuanced. To say that one reason is the only cause for mass shootings is not appropriate. Below is a list of motivations sourced from the Mass Shooter Database.

Table showing the motivations of mass shooters, including racism, religious hate, misogyny, homophobia, employment, economic, and legal issues

This table includes percentages of shooters motivated by these factors, such as targeting specific racial or religious groups. — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Myth: Violent video games are to blame for mass shootings

Violent video games have been a popular scapegoat for mass shootings, but the data does not align with this myth. Only 14% of mass shooters played violent video games according to the Mass Shooter Database.

Table showing data on video game use among mass shooters, including those who played violent video games, unspecified video games, or none at all. Data also includes shooters born before video games were available, with percentages for each category. — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Individualism in Mass Shootings

“One of the frustrating things is people are looking for the profile of the mass shooter, right? And what our research is saying is there’s not really a profile, but there are pathways.”

In America, there exists the notion that if an individual works hard and does what they are supposed to do, they will be successful. Unfortunately, those who find themselves in crisis are often not living up to this ideal. Some of these individuals look for who they can blame for their plight, which leads to intense anger against that individual or group. Mass shootings target the individual, group, or whoever is to blame for their grievances. For perpetrators, feelings of shame, isolation, hopelessness and depression often predate identification of a grievance, which they can then point their anger towards. So, whereas, the types of grievance and anger pointed outward vary, shame, isolation, hopelessness and depression is a common pathway.

Online Communities Worsen the Problem

Human beings are naturally attracted to ideas and frameworks of thinking. In response to isolation, people look for comradery to support their own frameworks. For example, in the last 20 years, some mass shooters have shared their desire for getting involved in a mass shooting on social media. It is common for people in crisis to seek answers through a community with similar predicaments, which aids in finding models of behavior.

Unfortunately, the internet is readily available with communities, answers, and examples of others who have walked the path of violence. The issue is that not all information is beneficial. Similar to how looking up symptoms on the internet can provide worst-case scenario diagnoses, an individual who feels isolated and hopeless can easily find poor examples of how to deal with their crisis. Chat rooms and forums are filled with people willing to give their advice or express the same negative ideologies. While this creates a sense of comradery and community for perpetrators, the consequences are devastating.

Table displaying social contagion factors among mass shooters, including interest in past violence, relationship to other shootings, legacy tokens, pop culture connections, planning, and performance. Data shows percentages of shooters for each factor — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Finally, it is common to leak the plan for a mass shooting prior to the event. The data below tells the story of who they tell and when.

Table showing leaking information patterns among mass shooters, including social media use, methods of leakage like in-person or writing, and whom the information was leaked to, such as family, mental health professionals, coworkers, or police — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Mass Shooting Prevention

Connection

Isolation is often the last phase a person in crisis goes through before committing a mass shooting. All of the mass shooters interviewed agreed that intervention was possible. Therefore, we conclude that connecting with people who exhibit concerning changes in behavior such as isolation can be life-saving.

Sharing on Social Media

Be conscientious of what you share on social media. Sharing clips or stories that have to do with mass shooters will increase their attention and publicity, which can encourage a last-stand mentality for those who are already toying with the idea.

Gun Safety in the Home

Make sure any weapons in the home are safely secured so that they are inaccessible to children and anyone who may be a danger to themselves or others.

Crisis Intervention Training

Individuals who are on the pathway to becoming a mass shooter will certainly need professional mental help, but everyone is able to act as a barrier to mass shootings. With skills in crisis intervention, one is equipped to navigate discussions with individuals showing signs of being in crisis. These interventions may prevent the person from making decisions that could harm themselves or others.

Better Reporting Methods

Institutions need to give employees, teachers, and students a better way to report possible behavioral red flags that do not result in punitive-only responses. Both teachers and students are rightly concerned about reporting suspicious behavior, because they do not think the response will be helpful or are afraid of being ostracized themselves. Reporting negative behaviors should be met with a mental health check-in rather than immediate punishment, which can increase the chances of retaliation.

More Mental Health Professionals

Schools are woefully understaffed with mental health professionals. Counselors must have the time and space to intentionally connect with students before they are overcome with shame, hopelessness, and anger.

Combatting Hopelessness

It can be easy to lose hope with every mass shooting that is reported, but refusing to give up and committing to an attitude that does not give celebrity status to perpetrators is an essential step toward prevention.

Conclusion

“Only when you understand those stories can you really start to appreciate where people are at and then you can move towards prevention and that’s the goal.”

The main focus of The Violence Project: How to Stop a Mass Shooting Epidemic is to show that there is something we all can do to help prevent mass shootings. While legislative action may be required in certain areas, we must start working as a society towards preventing these crimes rather than reacting to them. The Mass Shooter Database reveals that there is no cut-and-dry profile of these shooters but rather a much more nuanced path to becoming a perpetrator. We must stop turning these individuals in crisis into pseudo-celebrities, because this will only encourage copycats to do the same. Being aware of people who demonstrate signs of shame, hopelessness, depression and isolation is crucial in preventing shootings from taking place. We must remember there are always opportunities for prevention. If you are a mental health professional, you are part of the solution and can play a vital role. But we also must think outside our offices and hospitals to bring forth systemic change that rid our society of these tragic and all-too-common events.

Supplemental Data

Table showing location and scene data for mass shootings, including region, urban vs. rural areas, types of locations such as schools, workplaces, and houses of worship, and whether the shooter was an insider or outsider. Data includes percentages.

Table showing crime and violence data for mass shooters, including criminal records, prior homicides, history of violence, domestic abuse, sexual offenses, gang and terror group associations, hate group involvement, and bullying.

Table showing resolution of cases for mass shooters, including on-scene outcomes, attempts to flee, use of insanity defense at trial, and criminal sentences such as death penalty, life without parole, life imprisonment, hospitalization — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Table showing firearm data used by mass shooters, including weapon classification, caliber, gun modifications, use of extended magazines, and timing of gun acquisition relative to the shooting. Data includes percentages for each category.

Table showing firearm purchase methods by mass shooters, including legal and illegal purchases, unregulated sales, straw purchases, theft, gifting, and assembly with legal parts. Data includes percentages for each method used to obtain firearms. — This table was compiled from analysis of the database: (2021. Mass Shooter Database. Version 4.0. Retrieved from: www.theviolenceproject.org)

Acknowledgements:

This article was supported by “Mental Health Education & Research”.

Episode 123: Mass Shootings: An Interview with Criminologists Drs. Jillian Peterson and James Densley, the Argument for Data-Driven Nuance, and Steps for Prevention