Mass Shooters and the Psychopathology Spectrum

Are most individuals who carry out mass shootings “mentally ill?” Many in the general public—and some mental health professionals—continue to claim they are.1 This claim persists, despite findings to the contrary by forensic psychiatrists and several official investigations.2

It is clear that the disagreement has both empirical and conceptual components. On the one hand, we have empirical research looking at the prevalence of “serious mental illness” among those who have carried out mass shootings (usually defined as involving four or more victims).

In general, the best available research finds very little clinical evidence that most mass shooters have suffered from serious mental illness—usually taken to mean schizophrenia and related psychotic disorders; bipolar disorder; or major depressive disorder.3

On the other hand, many in the general public and the media seem to view the concept of “mental illness” much more broadly than do most forensic psychiatrists or experts in violence assessment. The question often put to psychiatrists by those in the media is, “How can someone who randomly shoots 10 or 20 people not be mentally ill? If that’s not mental illness, what is it?”4

The Nature of Mental Illness

The disagreement is not reducible to a naive “mistake” on the part of the media or the general public. That is, a satisfactory response to the question posed above cannot be a dismissive, “You simply don’t understand what mental illness is!” The problem is much more complex. It calls upon us to invoke Plato, whose reference (in the Phaedrus 265e) to “carving Nature at its joints” has fueled scientific controversies for 2,500 years.

What Plato was conveying in his “carving” metaphor is summarized by Matthew H. Slater and Andrea Borghini; specifically, Plato believed in “. . . the objective, independent reality of many different natural kinds of things. The members of such kinds would be the meat between the joints along which good theories cut.”5

Our modern-day debate regarding the “nature” of mental illness is a direct outgrowth of Platonic philosophy. As philosopher Kelso Cratsley has put it, Much of the current debate hinges on whether mental disorder should be understood as relatively discrete categories of illness or as dimensional gradations of symptoms that cut across traditional taxonomic boundaries.”6

In contrast to the notion of “natural kinds” or distinct categories in the realm of psychiatric disorders, there is “…growing evidence point[ing] to the superiority of a dimensional approach to the science of mental illness.”7

For example, it is possible to aggregate psychiatric symptoms into three domains along a dimension of psychopathology: 1) externalizing, 2) internalizing, and 3) psychotic experience.8 My colleagues James L. Knoll IV, MD, and J. Reid Meloy, PhD, explicate this model in a companion piece that appears in Psychiatric Times.

In my view, the Platonic concept of discrete categories or “natural kinds” is not well-suited to psychiatric illness or, indeed, to most phenomena in the realm of clinical medicine. As Dr Kenneth F. Schaffner notes,

The notion that the entities that are fundamental in a scientific area need to be discrete and separable is an idea that works well in some sciences such as physics and chemistry. But these types of entities are rarely found in biology . . .9

A Continuum of Emotional Disturbance

In this essay, I argue against a discrete, binary notion of “mental illness” or “mental disorder”—(ie. as a category completely distinct from “mental health”). Instead, I develop the concept of a continuum of mental, behavioral and emotional disturbance. Despite its categorical approach, the DSM-5 is by no means hostile to this view; stating, for example, that “The boundaries between normality and pathology vary across cultures for specific types of behaviors . . . hence, the level at which an experience becomes problematic or pathological will differ.”10(p.14)

With the aim of providing a heuristic model, I examine three broad divisions along the continuum of pathology, with one subtly grading into the other: transient, stress-related emotional turmoil; persistent emotional disturbance (PED); and mental illness/disorder.

I then apply these broad divisions to the status of the “mass shooter.” I argue, in effect, that most mass shooters fall roughly (but not invariably) in the middle of this continuum, ie, somewhere between “transient, stress-related emotional turmoil” (on the far left); and “mental illness/disorder” (on the far right).

I call this middle ground of psychopathology, “Persistent emotional disturbance.” And, while PED cannot be considered an instantiation of “mental health,” neither does it conform to psychiatry’s construct of “mental illness”—at least, not to our usual understanding of “serious mental illness.”

The diagram below shows how—as we move from left to right—the “disease-like properties” of the condition gradually increase.

I now elaborate on these three major divisions, with the caveat that these are not “categories” in the Platonic sense, or in the sense employed in DSM-5; rather, they represent progressive but subtle gradations of psychopathology.

Transient, Stress-Related Emotional Turmoil

Transient, stress-related emotional turmoil (TSRET) is familiar to nearly everyone and might even be considered emblematic of “the human condition.” It generally occurs in the context of major life events (both positive and negative); interpersonal conflict; or significant loss.

Although emotional reactions in these contexts can be intense, they are not inherently pathological and rarely cause significant or prolonged dysfunction. For example, following bereavement (the death of a loved one), it is “normal” to experience a range of strong and sometimes conflicting emotions.

These may fluctuate from “shock, anguish, loss, anger, guilt, regret” to more positive emotions, such as “relief, joy, peace, and happiness that emerge after the loss of an important person.”11

“Uncomplicated bereavement” (included in the “V” code section of DSM-5) differs in important respects from pathological states, such as “complicated grief” and major depressive disorder.11

TSRET may also be related to the person’s developmental stage, as we see in many psychologically “normal” adolescents and teens. Thus, as McLaughlin and colleagues12 note, the adolescent years are typically characterized by frequent and intense emotions; elevations in emotional and physiological reactivity; and greater emotional lability than are typical in either childhood or adulthood.

Moreover, “Compared with children and adults, adolescents also experience more intense emotions in both positive and negative domains.”12 Impulsive and sometimes risky behaviors are a common accompaniment of adolescent emotional turmoil. Although these emotional and behavioral features are not inherently pathological, adolescence is nevertheless a period of increased risk for psychopathology.12

Persistent Emotional Disturbance

In this portion of the continuum, we find individuals with more chronic and severe emotional problems, though still falling short of clinically significant mental illness. However, in some instances, the line between characterologically-based PED and full-fledged DSM-5 personality disorder becomes exceedingly fine, and this may indeed be the case with a subgroup of mass shooters.

By way of describing the psychological profile of the prototypical mass shooter, consider the following composite case.

Case Vignette

“Tyler” is a 19-year-old, single, unemployed high school dropout. Middle-school and high school records show that Tyler was often the target of bullying by older boys, who often teased Tyler about his slight build and high-pitched voice.

He was working as a short-order cook and doing various “odd jobs,” but was recently fired, after getting into a heated argument with his boss.

For most of his life, Tyler has felt like “the odd man out” and that he’s always gotten “the short end of the stick.” He posts angry rants regularly on social media, arguing that “the whole damn system is stacked against me,” and complaining that “it’s always the minorities that get all the goodies, even though they shouldn’t even be in this country!”

Tyler has long held a grudge against the high school he attended, accusing the administration of “targeting me for oppression and exploitation” and fantasizing about “a revolution born in blood to overthrow the elites.”

On social media, Tyler recently wrote, “I’m the only true-born leader who can purify this world of its filthy elements.” He has made a careful study of mass shootings in the U.S. and expresses admiration for the shooters, writing, “These are the true soldiers of the revolution.”

For several years, Tyler has been obsessed with firearms and ammunition, and has recently entertained fantasies of “shooting up” his former place of employment.


I suspect most readers—quite understandably—will find Tyler’s feelings and beliefs frightening and disturbing. Yet there is a good chance that, examined clinically, Tyler would not be diagnosed with a DSM-5 mental illness. To be sure: Tyler is hardly a model of mental health. He is what many psychiatrists would call “emotionally disturbed” but not clearly “mentally ill.” His worldview is one of anger, resentment, victimization, and narcissistic grandiosity.

But Tyler is likely not psychotic or suffering from what psychiatrists would consider “serious mental illness,” such as schizophrenia, bipolar disorder, or major depression. Though Tyler may have some features of one or more personality disorders (e.g., paranoid, borderline, or narcissistic personality disorder), he probably falls short of DSM-5’s Criterion C for general personality disorder (i.e., “. . . clinically significant distress or impairment in social, occupational, or other important areas of functioning”).10(p645)

The critical term here is clinically significant, which clearly requires careful judgment on the part of the psychiatrist, and on which point reasonable clinicians may disagree. On balance, I would place individuals with Tyler’s profile somewhere in the middle of the proposed continuum—perhaps somewhat “right of center.”

Mental Illness/Mental Disorder

This, of course, is the portion of the continuum with which psychiatry has been most directly involved, and I needn’t elaborate, beyond noting a few important elements of mental disorders illustrated in the Figure.

First, as we move to the far right of our diagram, the likelihood of “disease-like properties” increases. Specifically, the condition begins to become “clinically significant” and—as the DSM-5 notes—is usually associated with “significant distress or disability in social, occupational, or other important activities.”10(p20)

In addition, what I have called “core self-regulatory functions” decline steeply as we move to the far right. This includes the person’s ability to “reality test;” maintain impulse control; engage in rational decision-making; carry out activities of daily living; and—to use Dr Robert Daly’s term—to secure one’s “prudential interests.”13

The more the person’s condition takes on disease-like properties, the greater the dysfunction and disability in these core self-regulatory functions. Finally, as we approach the level of clinically significant psychiatric disorder, we find properties common to disease and disorder throughout general medicine: high syndromal coherence; good inter-rater reliability (kappa); substantial predictive validity regarding course and prognosis of one who meets the diagnostic criteria; familial and/or genetic correlations; characteristic biomarkers or biological abnormalities; and substantial suffering and/or incapacity.14,15

Classic psychiatric disorders that meet all, or nearly all, these criteria include schizophrenia and bipolar disorder.


The central consequence of the continuum described here is that—based on the best available evidence—most mass shooters would not fall into the range of frank mental illness or disorder.2,3 This has critical implications not only for our everyday understanding of mass shooters, but also for forensic and legal determinations; for example, regarding use of the so-called “insanity defense” in cases involving mass shooters.

This is not to say that serious mental illness, including psychotic conditions, plays no role in mass shootings. It’s likely that a small percentage of mass shooters do have bona fide mental disorders of psychotic proportions. But most—like our composite character, Tyler—are profoundly unhappy people whose wrldview is shaped by “the 3 Rs”: rage, resentment, and revenge.

Accordingly, when we psychiatrists are asked by the media, “How can someone who randomly shoots 10 or 20 people not be mentally ill?” we can reply by pointing out two things: first, that there is a distinction, however nuanced, between PED and mental illness; and second, that horrific violence on a mass scale is well within the range of socially deviant but psychiatrically “non-disordered” human behavior.

Tragically, human history tells us that this has always been so.16

Acknowledgments:  Dr. Pies would like to thank Dr. James L. Knoll for his comments on an earlier draft of this article; Anna Chavez Ph.D for her comments on “emotional disturbance;”  Dr. Reid Meloy for his comments on Borderline Personality Organization (personal communication February 19, 2020); Dr. George Brownstone for stimulating discussion of these issues (personal communication, 8/30/19); and the editorial and artistic staff at Psychiatric Times.

Note: This article was updated from the original version that appeared in Psychiatric Times.


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11. Zisook S, Shear K. Grief and bereavement: what psychiatrists need to know. World Psychiatry. 2009;8(2):67–74

12. McLaughlin KA, Garrad MC, Somerville LH. What develops during emotional development? A component process approach to identifying sources of psychopathology risk in adolescence. Dialogues Clin Neurosci. 2015;17(4):403–410

13. Daly RW. ‘Sanity’ and the origins of psychiatry. Assoc Advance Philos Psychiatry Bull. 2013; 20(1):2-17.

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15. Pies R. What Should Count as a Mental Disorder in DSM-V?]

16. Knoll & Pies


Mass Shooters and the Psychopathology Spectrum

This article originally appeared in:

Psychiatric Times

It is reprinted here with permission.

Ronald Pies, MD

Dr. Pies is Professor Emeritus of Psychiatry and Lecturer on Bioethics and Humanities, SUNY Upstate Medical University; Clinical Professor of Psychiatry, Tufts University School of Medicine; and Editor-in-Chief Emeritus of Psychiatric Times (2007-2010).


APA Reference
Pies, R. (2020). Mass Shooters and the Psychopathology Spectrum. Psych Central. Retrieved on September 19, 2020, from


Scientifically Reviewed
Last updated: 9 Mar 2020
Last reviewed: By John M. Grohol, Psy.D. on 9 Mar 2020
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