Peter Langman, PhD

Continuing Education Information


Preventing school shootings is a matter of conducting thorough, ongoing assessments of potential perpetrators. This is generally done in schools by a threat assessment team comprised of individuals in several roles and positions, including psychologists. This article addresses the importance of access to information and information exchange, warning signs of potential violence, elements of a comprehensive threat assessment (including motive, means, and opportunity), and the role of life stressors that contribute to desperation and rage, and three psychological types of school shooters.

School shootings can be prevented. The current “best practice” for violence prevention in schools is to have a trained threat assessment team that can investigate behaviors that may indicate a risk of violence. The State of Virginia developed and adopted guidelines for student threat assessment (Cornell & Allen, 2011); research has documented their effectiveness in reducing various types of school violence (Cornell, 2013). School threat assessment teams typically consist of a school administrator, school security officer, psychologist (on-staff or external contract), and a student counseling service staffer (and possibly a lawyer, facilities director, nursing personnel and so forth). Whether or not psychologists work within the school, they can play an important role as part of the threat assessment process. This article discusses both logistical and clinical issues to help inform psychologists about their roles in threat assessment, as well as what to look for when evaluating potential perpetrators.

Though the term “student” is generally used in this article to refer to potential perpetrators, it is important to recognize that school shootings have been committed by current and former school employees, too, including staff members, administrators, and professors. Also, although this article uses male pronouns, it is worth noting that school shootings have been committed by girls and women, as well, though less frequently. Finally, this article will primarily assume the reader is a psychologist or other mental health professional working in the community, whether in an agency or private practice. There are some additional factors which might be relevant for psychologists employed in a school system as a school psychologist.

Decision-Making about Referral Acceptance

If you are asked to become involved in a risk assessment of an adolescent, among the first things you need to determine is what is being asked of you (and by whom). Are you being asked to join the school’s threat assessment team, or are you being asked to do a more routine psychological evaluation with some special attention to violence potential, or is this a referral for treatment? How broad or narrow will your input (and responsibility) be? A clear understanding of what is being asked of you is more important with a referral involving potential violence as compared to a routine clinical referral for anxiety or depression.

If the initial contact is someone from the school system, you need to consider whether the primary client is the school system or the individual to be evaluated. You need to determine the urgency of the evaluation and feedback needed by the school, whether a written report or a physical meeting at the school is desired, and what contact with and involvement of the parents has already occurred. Is a one-time evaluation being requested, or is the school expecting an assessment and then treatment?

If the initial contact is by the parents of the adolescent, you need to consider the nature of their primary request. Are they calling you because the school told them that they had to do so, or are they calling you because they are in some degree of crisis after a meeting with school personnel and the concerns raised about their adolescent? Do they agree or disagree with the school’s concerns?  You need to determine whether a written report is expected by the school or whether the parents want you to attend a later meeting at the school as part of their request. Does the parent want an evaluation to meet a specific requirement of the school, or does the parent seek assessment and treatment of their child? Have they independently had concerns about their child?

Once you have a clear understanding of the nature of the referral and the expectations of your subsequent professional actions, you need to determine whether this is an appropriate referral for you to accept. Can you perform the activities requested of you in a timely manner that is responsive to the urgency of the situation and the needs of the school and the family?

Are you adequately trained and experienced to fulfill the requests being made? If the psychological evaluation being requested is of a fairly general nature seeking routine information about personality style, social engagement, reactions to authority figures, and family relations, this is an evaluation that most general practice psychologists can do. If the evaluation request is more specific and involves making detailed predictions about potential for violence and the circumstances under which it might occur, you should consider the possibility of a referral to a psychologist who specializes in such evaluations.

If you agree to do a psychological assessment for threat assessment purposes (among other potential reasons), attention to information exchange, necessary releases, and the full cooperation of all parties is essential to establish before beginning the evaluation. If the school is the initial contact, have they prepared the parents for the referral and have they already started the process of securing permissions and mandates for easy and quick information exchange? If the parents are the initial contact, are they fully aware of and willing to agree to regular information exchange to and from the school—and will they sign the necessary releases to allow quick and easy information exchange? If the necessary paperwork to permit such rapid and frequent communication is not in place or cannot be put in place, you should consider not agreeing to do the psychological evaluation. Both the Family Educational Rights and Privacy Act (FERPA) rules and the HIPAA Health Privacy rules may be relevant, so permissions and releases that meet the requirements of both must be considered.

FERPA and Communication Issues

Community based psychologists have more knowledge and experience with HIPAA regulations, but are generally less familiar with FERPA rules. The school personnel should be requested to identify any relevant requirement which will need to be addressed. The FERPA requirements are as complex as the HIPAA regulations, but the school system should have experience with the FERPA rules and have policies to insure compliance.

The Family Educational Rights and Privacy Act (FERPA) is often misinterpreted, thereby blocking the flow of information. School officials may believe that FERPA prohibits any disclosure of student information. As a result, information is not shared among school personnel who have a legitimate need to be informed. This was noted multiple times in the review of the Karl Pierson incident at Arapahoe High School in Colorado in 2013. It was reported that, for example, “It appears from the case file that LPS [Littleton Public School] personnel, in general, and AHS [Arapahoe High School] staff and administrators, in particular, seemed to be confused about the FERPA” (Safe Havens, 2016, p. 25). This was such a problem that even their director of security did not have access to important student information.

FERPA does not prohibit a school official from disclosing information about a student if the information is obtained through the school official's personal knowledge or observation, and not from the student's education records.

Misunderstanding FERPA can also prevent a school from contacting local law enforcement regarding safety concerns. Though states vary in their laws regarding threatening speech, there are laws, for example, against “terroristic threats” in Pennsylvania and “menacing” in Colorado. Knowing such laws is important in preventing school shootings, because if threats cross the threshold of the law, police can become involved and take whatever steps are deemed necessary to maintain safety. For example, when Karl Pierson threatened the life of a teacher, the teacher was so afraid that he considered leaving his position to protect his life; despite this, however, he never contacted the police regarding Pierson’s menacing behavior.

In order to clarify how FERPA applies to school safety, the Department of Education released a document that states:

FERPA does not prohibit a school official from disclosing information about a student if the information is obtained through the school official’s personal knowledge or observation, and not from the student’s education records. For example, if a teacher overhears a student making threatening remarks to other students, FERPA does not protect that information, and the teacher may disclose what he or she overheard to appropriate authorities (Department of Education, 2007).

Understanding FERPA is important even for psychologists who do not work in educational settings, because attempts to get information from school personnel might be denied due to a misunderstanding of FERPA. Knowing how the law applies to threat assessment can make the difference between being able to conduct a thorough evaluation or not.

Attack-related behaviors . . . include[s] drawing a diagram of the school to determine the best location to carry out the attack; purchasing firearms and practicing with them; obtaining materials to make explosives and experimenting with making bombs; or writing a list of
intended victims.

Warning Signs that Trigger a Threat Assessment

There is a wide range of behaviors that should trigger a threat assessment (O’Toole, 2000). Though sometimes these are obvious, that is not always the case. Also, the term “threat” has more than one meaning and covers a variety of actions that might indicate impending violence. These behaviors will be discussed under the headings of threats, attack-related behavior, and leakage, but these concepts overlap and may be defined differently by different writers. For example, Meloy, Hoffmann, Roshdi and Goldimann (2014) examined eight warning signs for targeted violence.

Threats Made vs. Threats Posed

Not all school shooters make threats. But, of course, some school shooters do directly threaten their intended victims. For example, Robert Flores at the University of Arizona in 2002 reportedly threatened a professor when he said, “You better watch your back if you’re going to flunk me.” This was a direct, though non-specific, threat to a woman whom Flores did indeed end up killing. Andrew Golden, in the 1998 Westside Middle School incident, told his peers, “You are all going to die.” These are explicit threats.

In many cases, however, the perpetrator never threatens the intended victims; rather, his behavior poses a threat through what is called “attack-related behavior” (Fein, et al., 2002). This could be through private behaviors that become known or public behaviors such as online posts and conversations with peers. However, the absence of direct threats to intended victims does not mean that the student is not at risk for committing violence.

Attack-Related Behaviors

Attack-related behaviors are actions that indicate someone is planning to commit an attack. This includes drawing a diagram of the school to determine the best location to carry out the attack; purchasing firearms and practicing with them; obtaining materials to make explosives and experimenting with making bombs; or writing a list of intended victims. Large-scale attacks are not impulsive; they are the product of weeks, months, or even years of fantasizing, thinking, and planning.

Thus, if a student is being investigated due to a threat or other behavior of concern, it is important to ask about plans they might have for becoming violent, as well as access to weapons, and possible intended targets. Students who are thinking of committing attacks might not want to answer these questions or might lie, but if they are at all ambivalent about what they are thinking of doing, they may well disclose this information.


Leakage refers to a wide range of circumstances in which perpetrators leak their violent intentions. For example, Michael Carneal, in the 1997 Heath High School incident, warned his friends to stay away from the school lobby on the morning after Thanksgiving break. Brenda Spencer, in a 1979 Cleveland Elementary School incident, bragged to friends that she was going to do something that would get her on television. In these cases, the perpetrators may not have revealed the specific nature of their upcoming actions, but if threat assessments had been in process and their peers revealed their statements, that would have been critical information. In an example of more explicit leakage, Kip Kinkel tried to recruit a peer to join him in his attack.

In some cases, students leak their intentions in their school assignments. A few weeks before the attack at Columbine High School, Dylan Klebold handed in a short story about a man who kills a group of students. The killer in the story was 6’4”, left-handed, and wore a black trench coat. Klebold himself was 6’4”, left-handed, and wore a black trench coat. In addition, the story describes the mass murderer as “god-like” and the narrator of the story states that he understands the man’s actions.

In addition, Eric Harris and Dylan Klebold made a movie for one of their Columbine classes in which they are hired by another student to come to school and kill people. Michael Carneal, in the 1997 Heath High School incident, wrote a graphic short story about a boy named Michael who tortured and killed students. Making this example even more disturbing was the fact that the killer was named “Michael” and the names of students being killed in the story were the names of actual students in the school. Thus, student assignments need to be explored as part of a threat assessment, and not simply dismissed as creative expression or fantasizing.

The Failure to Respond to Warning Signs

It is not uncommon for school personnel or others (including students) to be aware of warning signs and to fail to take appropriate action. Research is ongoing regarding the conditions under which students do and do not report threats and other potentially troubling behavior by fellow students (c.f., Millspaugh, Cornell, Huang, & Datta, 2015). Reasons for non-reporting by school staff may include simply not accepting that the person in question is capable of violence, or a conviction that “it can’t happen here.” In the aftermath of attacks in school settings, there have often been comments by local people that they never thought that such a thing could happen in their community. Students may not report warning signs because of social pressure not to inform on a fellow student, or a fear of being embarrassed about raising a potentially problematic situation when it is later assessed that no problem exists. It is important to avoid such complacency and to carry out a thorough investigation.

It is also critical to investigate and evaluate the actual behavior, possible motives, and potential for action—and not simply dismiss a problematic behavior because of the social standing of the family or personal connections with them. This is true no matter who the person is, whether the son of the principal or chief of police.  In 1998, after Kip Kinkel’s attack at Thurston High School, the assistant principal commented, “The rules we set up were ignored when the moment of truth arrived. They were not followed because, quite simply, he was Kinkel” (Langman, 2009, p. 181). What was the significance of his being Kinkel? Both of his parents were teachers, and his father had taught at Thurston High School for many years. As a result, even after Kinkel was found with a loaded gun in his locker, there was no investigation to see if he were planning a rampage attack. He was arrested and released, and came back to school the next day and shot twenty-seven people. The assistant principal stated, “Instead of considering the fact of the gun, they [the administrators] considered the family of the boy who was caught with it.”

School-based psychologists have one advantage over community-based psychologists in that the school psychologists have daily contact with students, teachers, and administrators who formally and informally report on the conduct and behavior of students. The school-based psychologists also have ready access and authorization to interview all relevant students and staff around a potentially threatening situation or individual, whereas community-based psychologists need to set up a collaborative relationships and arrangements with school personnel in order to provide a full range of information and perspectives, if that is needed. The school-based psychologist can also more easily monitor the behavior of a given student, at least during school hours.

The role of a psychologist on a threat assessment team is to help make the actual behaviors and verbal statements clear and to help illuminate the possible psychological significance and motivational aspects behind them.

Some Aspects of a Threat Assessment

As with any psychological evaluation, it is necessary to obtain an overview of the individual, the unique experiences of their life, their family history, and the major social and academic events so far in their life.  It is important to have an overall context of their current and past family and social life and experiences, within which to understand and consider the current troubling comments and behavior. Psychological testing should be an aspect of the overall evaluation, whether the MMPI or the MCMI or another general psychological assessment instrument. The more specialized or targeted aspect of a threat assessment considers the thoughts, feelings, and actions directly related to the possible future violent behavior.

The role of a psychologist on a threat assessment team is to help make the actual behaviors and verbal statements clear and to help illuminate the possible psychological significance and motivational aspects behind them. The direct threat assessment most generally begins with a review of the words, statements, actions, and behaviors that triggered the evaluation process. These are the threats, attack-related behaviors and leakages, as described above, regarding the present situation. This includes possible targets, the potential modes of violent behavior, and the conditions under which they might occur are considered. Table 1 presents some of the main topics areas that need to be explored.

Based on his words and actions, what motives and goals might the student have? What is the intent and purpose of any possible attack? Does the student have the means and capacity to carry out the act? Does the student see violence as an acceptable or desirable way to resolve problems?

These are simultaneously both general and specific questions. These questions are seeking to understand the nature of the threat, and to some degree the probability of it occurring in light of the available means, available targets, and the student’s general problem-solving style and frustration-management style.

As noted in the earlier examples, the threat assessment team needs to explore and consider earlier behaviors and interests of the student being assessed. One needs to determine whether the student has a grudge or grievance, and, if so, determine whether it is broad and general or very targeted toward a given person or type of situation. This information can come from the student, but whatever the student reports needs to also be compared and contrasted to what other students, teachers, and parents report. It is essential to determine whether the student has shown interest in online reports of previous school attacks, and whether the student is keeping a journal of thoughts and plans for possible action (and even has acquired the means for attack and/or practiced using those means).

. . . threat assessments are not once-and-done actions. They are dynamic processes and the risk level can change suddenly.

Role Models

One further area to investigate during a threat assessment is the presence of role models for violence. This can include characters from movies, books, or video games, as well as actual people, such as Hitler or Eric Harris. Many younger shooters, meaning those in their teens or early twenties, have found role models for violence, with Eric Harris being the most common (Langman, 2016b). Evidence of such role models, particularly in conjunction with warning signs and major life stresses may increase the risk.

Levels of Risk

In some cases, the warning signs will be clear enough to prompt quick intervention. In other cases, however, the threat assessment team might be left with a concern about safety but no evidence of an imminent threat. It can be helpful to view the evidence in light of a sequence of stages that perpetrators typically move through, from fantasy to planning to execution of the attack.

For example, over two years before his attack, Eric Harris (Columbine High School) recorded his vision of destroying cities and eliminating humanity from the planet. At this point, he was at the fantasy stage, engaging in unrealistic and grandiose thoughts about mass destruction. If a threat assessment had been conducted at this point, Harris would probably have been seen as a disturbing character, but there was no evidence of an actual, achievable attack plan. The fantasies of destruction were either vague or unrealistic.

In contrast, the Finnish school shooter Pekka-Eric Auvine, in the 2007 Jokela High School incident, posted a message online in which he stated the date of his attack, the location, his own identity, and even the weapon he would use. Unfortunately, he did not post this until the morning of the attack, leaving virtually no time for people to see it and intervene.

What these two examples illustrate is that the more detailed the plan, the more imminent the attack. If the attack is going to happen at some unspecified place and time in the more or less distant future, and the method and means to carry out the attack are unknown or unavailable, the risk of imminent violence is relatively low. If, however, a student tells a friend that he is going to shoot up the cafeteria with his father’s shotgun on Monday, the presence of specified time, place, method, and access to means makes this an extremely imminent risk.

It is also critical that threat assessment teams not dismiss concerns about a student who may only be fantasizing about violence. The fact that he may not have a detailed plan does not mean that he will not develop such a plan. For example, when Karl Pierson impulsively yelled a threat about killing his teacher, he probably had no plan in place. He did not know when he would commit the attack and did not yet have the weapon he would use.

While it is obvious that any student who eventually became a school shooter went through the fantasy, planning, and action steps or stages, it does not mean that everyone who fantasizes about hurting or killing someone will eventually do so. Fantasizing predicts fantasies. Thinking predicts thinking. Planning is more active and likely involves some initial actions, and, hence, it is more likely to predict other action.

Follow-up re-assessment or monitoring is important in determining whether there is a change in the risk of violence. A student may start with fantasies of violence, but end up committing murder.  The lesson learned here is that threat assessments are not once-and-done actions. They are dynamic processes and the risk level can change suddenly.

Life Circumstances

No one whose life is going well wakes up one day and decides to commit mass murder. There are typically multiple disappointments, rejections, failures, and other stresses that put people on the path of violence. For younger shooters, these factors include romantic rejections, academic failures, disciplinary actions, and legal involvement. For older shooters, in addition to romantic rejections, there may be marital failures, as well as legal involvement, occupational failures, and military rejection. A threat assessment investigation should look for life stressors that could cause people to be so enraged or desperate as to be at risk for violence.

The threat assessment team (and the psychologist) needs to consider how the student is coping with the stress in his current life, including consideration of all areas of life (school, home, social, academic, and, if relevant, work). Is this coping fully effective, partially, or not at all effective? Consideration of recent changes as well as long-standing patterns should be undertaken. Is there evidence of a recent failure, loss, or change in status and standing (at school or at home)? Is there evidence of the student being bullied, recently or over the course of many years? Does the student feel that his life is hopeless, such that he is desperate or despairing? Is the student seen as suicidal, again, presently or in the past?

In the case of Karl Pierson, his attack was triggered by his rage at being demoted from his leadership role on the debate team. But, this was combined with his history of poor coping with repeated failures with girls, as well as his grades precipitously dropping so low that he was in danger of not graduating. Non-graduation would have eliminated his hope of attending West Point, and probably eliminated his military aspirations. All of these factors represented a severe blow to his grandiose sense of self. In summary, Pierson was failing in multiple life domains (intimacy, academics, and future career), with the immediate trigger being the blow to his identity posed by his demotion from captain of the debate team.

Assessment of Positive and Supportive Elements

A threat assessment should also consider whether there are positive indications of interpersonal supportive elements and individuals in the student’s life. This should include considerations of both adults and peers.

Does the student have at least one relationship with a non-judgmental adult who the student believes will listen to his struggle and try to understand and support him? This could be a parent, but it also could be a teacher, coach, neighborhood friend/mentor, or someone at his church.  Can the student confide in this adult, and trust that he or she will not judge him or jump to conclusions about him, his feelings and reactions, and his fantasies? Do the most central adults in the student’s life support non-violent means of resolving conflict? Students with at least one trusting relationship with an adult are less likely to commit violence and more likely to be optimistic and attempt more effective means of problem solving.

Does the student have at least one positive relationship with a peer who is doing well in school and socially, who exhibits positive coping behavior and effective problem solving skills? This is one aspect of the broader question of the degree of “connectedness” (or lack thereof) that the student has with his same-age peers. Students who feel generally alienated from their peers or rejected from most social events with their peer group are at greater risk, particularly if they primarily interact with a small group of similarly rejected individuals who focus on violent fantasies and revenge. Having at least one friend who is a real role model of successful living may prevent someone from pursuing violence.

Role of Parents

Enlisting the cooperation of the parents can be critical to monitoring changes in potential risk and maintaining safety. Parents can play important roles in monitoring the whereabouts and activities of the student, keeping an eye on who the student associates with and what websites he visits. As noted, threat assessments capture a moment in time, and follow-up assessment should be considered. It is important to educate parents about warning signs and changes in warning signs, so they can play as active role in monitoring their student’s behavior and requesting follow-up assessments as necessary.

Students with at least one trusting relationship with an adult are less likely to commit violence and more likely to be optimistic and attempt more effective means of problem solving.

Though no parents of a school shooter knew that their child was planning to commit mass murder, some parents reported knowing information that could easily have warranted increased supervision. For example, Kip Kinkel’s parents (and Eric Harris’s parents) knew their sons built bombs, but apparently they never conducted room searches after making this discovery. If they had, they would have found more bomb-making materials, firearms, and journals expressing their homicidal thoughts.

In a more extreme case, the parents of Alvaro Castillo knew that he was obsessed with the Columbine High School massacre. In fact, Castillo’s mother drove him from North Carolina to Littleton, Colorado for a pilgrimage to Columbine High School, the house Eric Harris had lived in, and the pizza shop where he had worked. While in Littleton, Castillo bought a black trench coat in imitation of Harris. If his parents had searched his room they could have found his journal where he wrote about his plans to commit a school shooting.

Karl Pierson also kept a journal where he outlined his plans for mass murder and listed his intended targets. He had researched the Columbine attack in books and online. Unbeknownst to his parents, he bought a gun and obtained materials to build Molotov cocktails. Despite having concerns that he presented a risk of violence, there is no evidence that the school recommended that Pierson’s parents search his room.

Even if school personnel do recommend a room search, however, it is not easy to convince parents that their children are potential mass murderers. Such conversations need to be conducted with sensitivity, emphasizing the desire to not only keep the community safe, but also to keep the student safe. Calmly explaining the reason for concern and the need to take precautions may help, but parents might still react with anger at what is perceived as an accusation against their children or a condemnation of them as parents. It is important to think carefully about how to present safety concerns to maximize the likelihood of getting the parents to collaborate in the effort to maintain safety.

Another challenge can be convincing parents who own firearms to remove them from the home. This can be presented as a temporary precaution, not a long-term requirement. Again, it is important to think carefully about how this can be presented. Similarly, parents may not react well to the idea that their children might benefit from mental health treatment, but, without parental support, the children are unlikely to receive services that might be crucial to their well-being and safety

. . . there are three psychological categories that the perpetrators typically fall into: psychopathic, psychotic, or traumatized, with
occasional perpetrators having traits of two of these categories.

Psychological Typology

In many threat assessment situations, the available evidence may be ambiguous. Perhaps a student makes a threat but it seemed to be in the heat of the moment with no intention of ever causing harm. Or maybe a student has a fascination with violence in general or Columbine in particular, but the investigation has not uncovered any plans to commit an attack. Besides monitoring the student for threats, leakage, and attack-related behavior, what else can be done?

Another course of action is to explore the psychological make-up of the student. After all, most people are not capable of gunning down other people in cold blood. In fact, Lt. Col. Dave Grossman has written about the inhibition soldiers often experience that prevents them from killing even in war:

The resistance to the close-range killing of one’s own species is so great that it is often sufficient to overcome the cumulative influences of the instinct for self-protection, the coercive forces of leadership, the expectancy of peers, and the obligation to preserve the lives of comrades (2009, p. 86).

If soldiers facing an enemy in combat cannot overcome their natural revulsion against killing, what is wrong with school shooters that make it possible for them to do what trained soldiers often recoil from?

Based on analyses of dozens of school shooters, there are three psychological categories that the perpetrators typically fall into: psychopathic, psychotic, or traumatized, with occasional perpetrators having traits of two of these categories (Langman, 2009; Langman, 2015). Though most people in these categories do not commit murder, a student who presents with threats, leakage, and/or attack-related behavior, and who also appears to be psychopathic, psychotic, and/or traumatized may present a greater risk of violence. This is another way in which a psychologist can contribute on a threat assessment team.

Psychopathic School Shooters

Psychopathy is a complicated concept, and because it is not a formal diagnosis there is no list of agreed-upon traits that define a psychopathic personality. The concept of psychopathic school shooters relies primarily on the work of Hare (1999) and Millon and Davis (1998).

Perhaps the central aspect of psychopathic shooters is their profound narcissism. They not only have a grandiose or inflated sense of themselves, but they are so self-focused that they have limited empathy for others. In fact, they are so entitled that they tend to believe that they ought to be able to do whatever they want, and as a result they have little patience for anything that puts limits on what they can do, such as social conventions, rules, or laws. They are easily enraged when they do not get what they want.

This attitude often leads to clashes with authority figures, including parents, teachers, administrators, and the police. Even when psychopathic shooters know that they have acted inappropriately or illegally, they often object to whatever consequences they receive and feel like they are victims of injustice. They may go through life accumulating a tally of all the injustices they believe they have suffered, holding onto these grudges and wanting revenge.

Not only do psychopathic shooters have little or no concern for the suffering they cause others, they sometimes are sadistic and seek experiences in which they have the power to hurt, and, ultimately, kill others. They may also be highly skilled at what Hare calls “impression management,” meaning they know how to make a good impression when it serves their purpose. This is the ability that makes con artists successful in deceiving people. Thus, psychopaths often succeed in hiding their violent intentions from the people in their lives.

Karl Pierson exhibited numerous psychopathic traits in the months leading up to his attack (Langman, 2016). He was easily enraged and had several episodes of inappropriate classroom behavior, including bullying his peers and being disrespectful to teachers. Many students and teachers noted his anger problems, and Pierson himself stated, “I become a monster when I’m mad” (Langman, 2016a, p. 3).

He was also narcissistic and described himself as “a psychopath with a superiority complex.” He did not accept the consequences of his behavior, and was so enraged by being demoted from captain on the speech and debate team that he became homicidal. Psychopathic shooters are so entitled that they become enraged when their desires are thwarted. Thus, demotion and rejection become motivations for murder.

Psychotic School Shooters

The term “psychotic school shooters” includes those with symptoms of either schizophrenia or schizotypal personality disorder. The central feature in this category is impaired reality testing. Most often this includes paranoid and grandiose delusions, but may also include hallucinations. Some perpetrators have not had clear delusions or hallucinations, but had other disturbed thoughts or evidence of impaired reality-testing, such as being confused about what was real, or wondering if they were really human.

Psychotic shooters sometimes exhibit other symptoms, such as disorganized thoughts or behavior, inappropriate or constricted affect, and poverty of speech. They often struggle socially and though they may have friends, they tend to feel profoundly alienated from those around them. This causes anguish and depression, as well as envy that sometimes turns to hatred of all those who appear to be succeeding where they are failing. This envy may be the driving force behind their violence. Alternatively, the violence may be motivated by paranoid delusions or command hallucinations.

Traumatized School Shooters

Whereas psychopathic and psychotic school shooters tend to come from basically stable, intact families, traumatized school shooters come from violent, dysfunctional homes. Common features include parental substance abuse, parental criminal behavior (sometimes to the point of incarceration), and absence of one or both parents, domestic violence, and the physical and psychological abuse of children. A significant number of traumatized shooters also endured sexual abuse, either in the home or elsewhere.

The attacks of traumatized shooters may be driven by anger at particular people they believe have wronged them, or can constitute a generalized lashing out against the world that has caused them so much suffering.

Finally, because of the severe family dysfunction, the children often experience frequent relocations and changing caregivers, moving from one relative to another and sometimes through multiple foster homes. These relocations often disrupted friendships and school performance and made it difficult for the children to achieve any sense of stability. Traumatized school shooters have been picked on at school more than other shooters, perhaps because they were often “the new kid.” Thus, for many of them, neither home nor school provided a safe haven.

The attacks of traumatized shooters may be driven by anger at particular people they believe have wronged them, or can constitute a generalized lashing out against the world that has caused them so much suffering. Jeffrey Weise, a traumatized shooter, summed up his life as “16 years of accumulated rage suppressed by nothing more than brief glimpses of hope, which have all but faded to black. I can feel the urges within slipping through the cracks, the leash I can no longer hold” (Langman, 2015, p. 76).

By themselves, features of the three psychological types of shooters (psychopathic, psychotic, and traumatized) should not be seen as warning signs of violence. When in the course of a threat assessment such features are discovered, however, this may indicate an increased potential for the student to be capable of carrying out an attack. It is the combination of these traits with threats, leakage, and attack-related behaviors that elevates the danger. This is particularly true when life events add fuel to the fire.


School shootings can be prevented by knowing what to look for and how to conduct a comprehensive threat assessment. Nekvasil and Cornell (2015) compared schools that used the Virginia Student Threat Assessment Guidelines with schools that did not use the guidelines or used locally developed procedures. Schools using the Virginia guidelines had lower short-term suspension rates, had lower levels of student aggressive behavior, and had discipline that was viewed as “fairer” by students. Teachers also reported feeling safer in schools using the Virginia guidelines.

Psychologists can play an important role on threat assessment teams through their understanding of psychological dynamics, life stressors, and motivations for violence. The general clinical skills needed in threat assessment are those already well known to any practicing clinical psychologist. What knowledge is unique to a threat assessment context is the more targeted attention to the specifics of successful versus unsuccessful coping with frustration, anger, and rage, as well as the specific life circumstances and events in the lives of potential school shooters. Motive, means, and capacity for violence are core issues in a threat assessment.


Peter Langman, PhD, is a psychologist in private practice in Allentown, PA. He is the author of the books, Why Kids Kill: Inside the Minds of School Shooters, and School Shooters: Understanding High School, College, and Adult Perpetrators. He maintains the website


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Table 1

Threat Assessment Exploration Topics

  1. What is the nature of others’ concerns about the student’s potential for violence?
  2. What ideas or intentions of aggression or attack has the student expressed?
  3. Has the student shown unusual interest in previous school shooters, school shooting incidents, mass violence, or weapons?
  4. Does the student view violence as an acceptable way to solve problems?
  5. Has the student developed and written an attack plan or acquired equipment or supplies necessary for an attack?
  6. Does the student have the skills, ability and means to carry out a possible attack?
  7. What are the student’s complaints, grudges, grievances, and motives?
  8. Who are the targets of the student’s complaints, grievances and anger?
  9. Has the student previously attempted to resolve the problem without success?
  10. Is the student experiencing hopelessness, despair, and desperateness?
  11. Is there evidence of factors which would increase or decrease probability of violence?
  12. Does the student have a trusting relationship with a responsible adult from whom the student can obtain support and advice and non-judgmental guidance?