Psychology of a Mass Shooter

Mass Shootings in Today’s World

I recently came across a paper I wrote while in graduate school.  I was very proud of the work I created and I remember it was very well received by my professor.  I was also reminded how passionate I am about the intersection between violence and mental health, and more importantly, education regarding this topic, which could potentially help solve some very challenging problems facing our country. I am sharing my research about mass shootings because it is an important issue that should be discussed.

Media Perception

Labeling the Problem

Mass shootings have received a significant amount of public attention, especially in recent history.   This epidemic is fueled by the media and the seemingly random locations of the attacks.  Public places such as schools, malls and movie theaters have become the settings of many of these shootings.  People are afraid these attacks could happen at any time and anyone could instantly become a victim.  This fear only feeds the demanding of a solution.

Mental Illness and Violence

Additionally, news reports shape how people view these individuals within the context of mental illness.  Research suggests that “news stories about mass shooters…heighten negative public attitudes about persons with [serious mental illness]… suggesting that the high volume of news coverage describing violent persons with [serious mental illness] could lead the public to view the population with [serious mental illness] as a threat to public safety (McGinty, Webster, Jarlenski, & Barry, 2014, p. 410).

However, Rosenberg (2014) notes “a large body of research shows that violence by people with serious mental illness, such as schizophrenia or bipolar disorder, is rare and accounts for approximately only 4 – 5% of violent acts” (p. 109).  Furthermore, when people with a serious mental illness are violent it is not in the context of a mass shooting. Rosenberg (2014) continues to point out “when people with mental illness are violent, it is almost always interpersonal (87%), typically occurs in the home, and the targets are usually family and/or friends” (p. 109).  There are exceptions to every rule.  However, generally, the media has wrongly depicted mental illness and mass shooters to the public.

Inside Their Minds

A Common Theme

Instead of focusing on internal causes, the media suggests external reasons for mass murders.  More than just access to violent video games and movies, mass shooters have many psychological characteristics that contribute to their crime.  It is important to differentiate these psychological
characteristics from clinical mental illness. These factors are common among many mass shooters, and include feelings of social isolation, narcissism, anger, and revenge.
Because of the fabricated notion of a mass shooting epidemic, the “public fears [demand] answers in hopes of providing some veneer that future events [can] be prevented, most typically through notions
of profiling, which [offer] the possibility of identifying likely shooters before the acts [are] perpetrated” (Ferguson, Coulson, & Barnett, 2011, p. 143).

However, prevention has proved difficult, especially when trying to label these individuals beforehand in such a profile.  Mass shooters share several qualities, but despite these commonalities, an effort to prevent future attacks through a general profile, gun control laws, and the mental health system will prove very challenging.

The Profile

Social Isolation

To understand the profile of a mass shooter, certain common features need to be addressed.  A reoccurring theme among mass shooters is the idea of social isolation, which factors prominently into their perception of being the victim of an unfair society. Knoll (2012) notes “the subjects had all been bullied or isolated as children, turning into loners who felt despair over being socially excluded” (p. 758).

However, this stated social isolation might just be a perception. Ferguson et al. (2011) make a notable point that “a large proportion (71%) perceived themselves as wronged, bullied, or persecuted by others”, and this may be slightly different than what actually occurred (p. 151).  The perceived injustice is more important than reality.  These individuals feel as though others are responsible for their outsider status and any sadness and anger created from the social rejection.

Killers internalize this apparent social alienation. As a result, these individuals develop a paranoid and “persecutory worldview, leaving them with a strong self-centered…character style” (Knoll, 2012, p. 764).  The concept of social isolation is very important when examining mass shooters as a whole, especially their emotional development.

Depressive Symptoms

This perception of social rejection causes many intense emotions within the individual.  Firstly, these offenders generally suffer from depressive symptoms.  Although they are rarely formally diagnosed, many express these traits.  For example, many mass shooters “had a history of suicide attempts or ideation in their past (78%), or a documented history of significant depression (61%)” (Ferguson et al., 2011, p. 151).  For these offenders, the depression could easily be initiated by the original social isolation from peers or family.

Resentment and Anger

Furthermore, this social isolation develops into a resentment that mass shooters feel towards society and their surroundings.  These individuals develop anger that reflects “feelings of persecution, resentment, and destructive envy” (Knoll, 2012, p. 776).  This anger then manifests itself in a desire for revenge.

The violent offender wants to carry out a form of payback for all the failures and inequalities they have experienced.  These “revenge fantasies are inflexible and persistent because they provide desperately needed sustenance to self-esteem” (Knoll, 2010, p. 90).  Virginia Tech shooter, Seung-Hui Cho and Columbine killers, Harris and Klebold are examples of this resentful style of offender wanting hostile revenge (Knoll, 2010).  This built-up anger motivates a desire for retaliation, which generally turns violent, leaving many victims.


For the shooter, the benefits of acting upon this anger and revenge are necessary due to their narcissistic style.  The concept of revenge and their narcissism are completely intertwined and ingrained in their personality.  Despite common understandings of the term narcissism, it actually results from, and acts as a defense of, a very fragile self-esteem. This unstable self-image is masked by grandiosity and an exaggerated sense of self-importance.

However, if they are to be criticized, as in the case of their perceived social rejection, the critique can be seen as a personal attack, resulting in anger and rage.  This narcissistic injury develops into aggression and revenge.  The idea of revenge and the eventual follow-through “serves as a defense against feelings of shame, loss, and powerlessness” (Knoll, 2010, p. 90).  Through revenge, these individuals are attempting to restore the grandiose self that was damaged by critique and rejection.

Desire for Power and Control

Additionally, these narcissistic offenders also use their revenge shootings to gain power that they never had.  
Fox and DeLateur (2013) call this the pseudo-commando offender, who kills for a sense of power, albeit unrealistic and false.  The mass murderers act upon a “vengeful rage [that] provides only pseudo-power, as it is merely a reaction to intolerable feelings of powerlessness and humiliation” (Knoll, 2010, p. 89).

This need for power may only be an emotional reaction, but it feels necessary for these offenders.  The killer’s “very public and arguably theatrical nature of mass murder as revenge speaks clearly to the offender’s need for recognition from an audience” (Knoll, 2012, p. 763).  In so many ways the offender gains “a sense of (pseudo) power and control by ruminating on, and finally planning out his vengeance” (Knoll, 2010, p. 90).  The individual lost this recognition through social isolation, and uses killing as a way to capture attention and reestablish power.

Many mass shooters die by suicide immediately following the attack, and see suicide as a final method to obtaining that lost concept of power and control.  These killers appear “to welcome death, even perceiving it as bringing them fame with an aura of power” (Knoll, 2012, p. 758).  This idea and need of power is important in building up the damaged self image and providing a motive for revenge.  This combination of narcissistic personality and rage is crucial in the psychology and drive behind mass shooters.


Although information and research on mass shooters is limited because many offenders die directly after or during the attack, we can learn from what they’ve left behind.  Many offenders reveal significant planning of the attack.  The preparation of the attack actually feeds their narcissism, giving them the sense of power before the actual incident takes place.

Mass murder rarely is the result of a sudden explosion of rage.  Plans are usually put into place after weeks or months of careful preparation (Fox & DeLateur, 2013).  Because these offenders are seeking vengeance, they generally have a specific target in mind.  A completely random attack is very unlikely.  Instead, the murderous assault usually is focused on “a primary target which itself can be a place, such as a company, a school, or an agency, while others are killed as surrogates” (Fox & DeLateur, 2013, p. 127). Sometimes the planning is even documented in journals and notebooks.  These journals can be graphic and include violent poems and essays (Ferguson et al., 2011).  Because the offender feels like
they have been terribly wronged and have something to prove, the amount of preparation is quite extreme. The level of planning from these offenders contributes to the sense of power and allows them to stay calm even in all the chaos they are causing.

If there is any hope of being able to identify mass shooters before an attack, it is important to have a correct picture instead of the misleading image that is currently being portrayed.

Hiding in Plain Sight

However, even with a more accurate picture, most mass shooters do not generate any obvious indications, and therefore attempts at finding these offenders prior to an attack is very unlikely.  The common characteristics that are often most visible to others, such as depression and social isolation, happen to many people that will never hurt another person, let alone commit mass murder.

Social isolation may seem to be the easiest identifying mark, however the social rejection takes place mostly within the individual’s mind.  These future killers may not be the most popular in school, but “only 12% had no friends at all” (Ferguson et al., 2011, p. 151).  Most of them were part of fringe peer groups, but still had a few friends.  This shows that the large majority of mass shooters did have at least a couple of friends, and therefore did not appear too different from the rest of their peers.

Fox and DeLateur (2013) recognize that “mass killers tend to share a number of psychological and behavioral characteristics, including depression, resentment, social isolation, the tendency to externalize blame, fascination with graphically violent entertainment, and a keen interest in weaponry.  However, these characteristics, even in combination, are fairly prevalent in the general population” (p. 133).  It is important to not over generalize a concept so as to avoid including more people than is necessary.

Risks of Over-identification

The supposed profile of school shooters, in particular, is just that.  These summaries “of school shooters carry considerable risks of over-identification” when attempting to apply them to the general population (Ferguson et al., 2011, p. 144).  With over-identification, comes the risk of labeling, stigmatizing and potentially offending those who really do not present a threat but have been considered prone to violence because of this profile.

Even the FBI has expressed doubts, “stating that it should be used only after an individual has made a threat in order to judge the credibility of the threat” (Ferguson et al., 2011, p. 144).  The large number of false-positives generated from this depiction of mass shooters can be harmful to those labeled, as well as taking away from the actual issue at hand of preventing further mass shootings.  Generally, mass murderers do not significantly stand out from the rest of the population making it very difficult to target only them prior to an assault.

Gun Control

Besides the attempts of preventing future mass shootings through the use of a profile, current gun control laws also make it difficult to stop upcoming attacks.  The Gun Control Act of 1968 and the National Instant Criminal Background Check System are two efforts put in place in attempt to prevent the sale of firearms to those seen as dangerous.

Gun Control Act of 1968

The Gun Control Act of 1968 was established to prohibit “gun ownership by any person who has been ‘adjudicated as a mental defective or committed to a mental institution’” (Rosenberg, 2014, p. 111).  While this does seem important, it does not apply to those who have voluntarily sought treatment.  Only those who have been involuntarily committed to a mental institution are prohibited from obtaining weapons under this law (Rosenberg, 2014).

National Instant Criminal Background Check System

The National Instant Criminal Background Check System (NICS) is the primary method for controlling access to firearms within the United States (Rosenberg, 2014).  Under this system, background checks are immediately conducted upon purchase of a firearm.  However, this operation “captures only individuals who attempt to purchase firearms legally” (Knoll, 2012, p. 775).  This law does not apply to people purchasing guns through private sales, and obviously illegal methods are not subject to background checks.

This is further complicated by the fact that “state-based NICS programs and their relevant statutes are not uniform. . . Prohibited persons in various states can range from those who received outpatient psychiatric treatment, to persons who have been civilly committed or found not guilty by reason of insanity” (Knoll, 2012, p. 775).  This lack of uniformity across states is not helping prevent gun violence.  The goal of these gun control laws is to attempt to diminish the access of firearms, however many dangerous people are still obtaining guns. Relevant reform needs to take place.

Legal Challenges

Purchasing Legally

In particular, these current legal efforts are not influencing the prevention of mass shootings.  Mass shooters generally don’t raise alarming red flags, appearing like regular individuals with no criminal or mental health records, and therefore they are still eligible to obtain firearms.  Most of these individuals “do not have criminal records or a history of psychiatric hospitalization.  They would not be disqualified from purchasing their weapons legally” (Fox & DeLateur, 2013, p. 135).

These people might appear slightly off, but “people cannot be denied their Second Amendment rights just because they look strange or act in an odd manner” (Fox & DeLateur, 2013, p. 135).  If minimum age requirements are met, these laws do not limit a mass shooter’s access to firearms.  These individuals generally have no problem obtaining firearms legally, however, there are other options as well.

Obtaining in Other Methods

Research has shown that “several mass shooters have used firearms purchased, borrowed, or stolen from a family member or friend” (Fox & DeLateur, 2013, p. 136).  Despite the law’s best efforts, “firearms still pass easily from legal owners to juveniles and others… such as felons or persons with mental illness” (Kellerman & Rivara, 2012, p. 549).  Even with these legal attempts to limit access to firearms, the availability of weapons to those considering a mass shooting has not been reduced.

Role of the Mental Health System

Besides attempts at gun control, psychological treatment may prove difficult in preventing a mass shooting.  These mass shooters are generally not brought to the attention of the mental health system beforehand, and therefore cannot benefit from any treatment.  It has been addressed that “few perpetrators had received mental health services in the past or been diagnosed with mental health problems”, despite probably needing that psychiatric treatment (Ferguson et al., 2011, p. 151).

These angry individuals have a “tendency to externalize blame and consider themselves as victims of mistreatment; mass murderers see the problem to reside in others, not themselves” (Fox & DeLateur, 2013, p. 135).  Since they do not believe they have a problem, the offender is very unlikely to seek help.  According to the perpetrator, “he or she desires fair treatment, not psychological treatment” (Fox & DeLateur, 2013, p. 135).

Stigma of Mental Illness

Since the offender does not see the need for mental health services themselves, this leaves only close friends and family to encourage them to be treated (Knoll, 2012, p. 774).  That only works however, if the offender has raised enough suspicion to begin with, which as we’ve learned, may not happen.  Increasing availability to psychological treatment most likely will not have a serious effect on preventing mass shootings.  The real issue resides in how people view the mental health system and mental illness in general.

Media Contribution

It is important to remember how the media has shaped the public perception of mental illness and violence.  There is a negative image around mental illness because of news stories and other media outlets. Rosenberg (2014) notes that “research suggests that mass shootings can increase mental health stigma, reinforce negative stereotypes that people with mental illness are dangerous and violent, and influence public policy, all of which can undermine treatment and recovery” (p. 107).

Mass shootings increase the public stigma against mental illness, which in turn makes mental illness a difficult subject to approach.  If people do not feel comfortable with the topic of mental illness, they are even more unlikely to seek therapy for themselves or others.  The problem really resides in how society views this common occurrence.  If there is any hope of a potential mass murderer seeking psychological treatment, society’s attitudes surrounding mental illness must change in order for one to feel accepted.  This is especially important for mass shooters who already feel like they are socially cast aside.


The recent focus on such tragic events has led to considerable fear, which has spurred a demand for prevention.  However, this prevention has proven to be a very difficult task.  These offenders seem to blend in with society, not raising too much alarm or suspicion as to warrant extensive concern.  Efforts have been made to create a sort of profile of a mass shooter, in order to facilitate identification prior to an attack.  This textbook summary incorporates many of the psychological characteristics shared among these offenders.  However, many other individuals within the community also share these traits.  The amount of false-positives is just too great, and it is unfair to label and stigmatize these innocent people.

Efforts have also been made through gun control legislation.  The Gun Control Act of 1968 and the National Instant Criminal Background Check System filter out people wishing to purchase a firearm if they are a convicted criminal or seriously mentally ill.  The laws are justified, however mass shooters normally do not fit these criteria.  Even if they did, there is still considerable access to guns through friends and family, not to mention obtaining through illegal methods.

The mental health community has also been looked at to help prevent mass shootings.  However, these individuals are generally not brought to the attention of the mental health system prior to an attack.  There is a social stigma surrounding the mental health system that makes people unwilling to seek out psychological treatment.  This stigma in combination with the offender’s denial of problems, keeps potential perpetrators out of the mental health system.  The efforts to prevent future mass shootings are far from over.  The legislature, law enforcement and the mental health systems will continue to look for solutions.

What Can We Do?

Until then, it is important to lessen the stigma surrounding mental illness in this country in order to more adequately provide the necessary treatment and services.  Part of this happens through education and sharing.  It’s hard to fix something if we don’t understand how it is broken.

There are many great groups out there tackling this very difficult issue. Try and educate yourself as much as you can on the topic. Consider donating or volunteering with a group making a difference. For more information check out:


Ferguson, C. J., Coulson, M., & Barnett, J. (2011). Psychological profiles of school shooters:                 Positive directions and one big wrong turn. Journal of Police Crisis Negotiations, 11(2),  141-158.

Fox, J. A., & DeLateur, M. J. (2013). Mass shootings in America: Moving beyond Newtown.       Homicide Studies, 18, 125-145.

Kellermann, A.L., & Rivara F.P. (2012) Silencing the science on gun research. The Journal of the American Medical Association, 309(6), 549-550.

Knoll, J. L. (2010) The “pseudocommando” mass murderer: Part I, the psychology of revenge and obliteration. Journal of the American Academy of Psychiatry and the Law, 38, 87-94.

Knoll, J.L. (2012) Mass murder: Causes, classification, and prevention. Psychiatric Clinics of North America, 35(4), 757-780.

McGinty, E. E., Webster, D. W., Jarlenski, M., & Barry, C. L. (2014). News media framing of serious mental illness and gun violence in the United States, American Journal Of Public Health, 104(3), 406-413.

Rosenberg, J. (2014). Mass shootings and mental health policy. Journal Of Sociology & Social      Welfare, 41(1), 107-121.

I am not an expert regarding this topic and am only sharing the literature research I conducted while in graduate school.