A new study by the U.S. Secret Service's National Threat Assessment Center (NTAC) says that a majority of school shooters showed warning signs before committing their crimes, and most of them were bullied.

The U.S. Secret Service National Threat Assessment Center (NTAC) studied 41 incidents of targeted school violence that occurred at K-12 schools in the United States from 2008 to 2017. The report offers an in-depth analysis of the motives, behaviors, and situational factors of the attackers, as well as the tactics, resolutions, and other operationally-relevant details of the attacks. The analysis suggests that many tragedies could have been prevented, and supports the importance of schools establishing comprehensive targeted violence prevention programs.

"The threshold for intervention should be low, so that schools can identify students in distress before their behavior escalates to the level of eliciting concerns about safety," the report says. "Because most of these attacks ended very quickly, law enforcement rarely had the opportunity to intervene before serious harm was caused to students or staff. Additionally, many of the schools that experienced these tragedies had implemented physical security measures (e.g., cameras, school resource officers, lockdown procedures). Prevention is key."

Some of the key findings from the study, and their implications for informing school violence prevention efforts, include:

There is no profile of a student attacker, nor is there a profile for the type of school that has been targeted: Attackers varied in age, gender, race, grade level, academic performance, and social characteristics. Similarly, there was no identified profile of the type of school impacted by targeted violence, as schools varied in size,location, and student-teacher ratios. According to the report, "Rather than focusing on a set of traits or characteristics, a threat assessment process should focus on gathering relevant information about a student’s behaviors, situational factors, and circumstances to assess the risk of violence or other harmful outcomes."

Attackers usually had multiple motives, the most common involving a grievance with classmates: In addition to grievances with classmates, attackers were also motivated by grievances involving school staff, romantic relationships, or other personal issues. Other motives included a desire to kill, suicide, and seeking fame or notoriety. "Discovering a student’s motive for engaging in concerning behavior is critical to assessing the student’s risk of engaging in violence and identifying appropriate interventions to change behavior and manage risk," the report says.

Many of the attackers were able to access firearms from the home of their parents or another close relative. While many of the firearms were unsecured, in several cases the attackers were able to gain access to firearms that were secured in a locked gun safe or case. 

Most attackers had experienced psychological, behavioral, or developmental symptoms: The observable mental health symptoms displayed by attackers prior to their attacks were divided into three main categories: psychological (e.g., depressive symptoms or suicidal ideation), behavioral (e.g., defiance/misconduct or symptoms of ADHD/ADD), and neurological/developmental (e.g., developmental delays or cognitive deficits). "The fact that half of the attackers had received one or more mental health services prior to their attack indicates that mental health evaluations and treatments should be considered a component of a multidisciplinary threat assessment, but not a replacement. Mental health professionals should be included in a collaborative threat assessment process that also involves teachers, administrators, and law enforcement," the report says.

Half of the attackers had interests in violent topics: Violent interests, without an appropriate explanation, are concerning, which means schools should not hesitate to initiate further information gathering, assessment, and management of the student’s behavior. 

All attackers experienced social stressors involving their relationships with peers and/or romantic partners: Attackers experienced stressors in various areas of their lives, with nearly all experiencing at least one in the six months prior to their attack, and half within two days of the attack. In addition to social stressors, other stressors experienced by many of the attackers were related to families and conflicts in the home, academic or disciplinary actions, or other personal issues. "All school personnel should be trained to recognize signs of a student in crisis.Additional training should focus on crisis intervention, teaching students skills to manage emotions and resolve conflicts, and suicide prevention," the report says.

Nearly every attacker experienced negative home life factors: The negative home life factors experienced by the attackers included parental divorce or separation, drug use or criminal charges among family members, or domestic abuse. "While none of the factors included here should be viewed as predictors that a student will be violent, past research has identified an association between many of these types of factors and a range of negative outcomes for children," the report says.

Most attackers were victims of bullying, which was often observed by others: Most of the attackers were bullied by their classmates, and for over half of the attackers the bullying appeared to be of a persistent pattern which lasted for weeks, months, or years. "It is critical that schools implement comprehensive programs designed to promote safe and positive school climates, where students feel empowered to report bullying when they witness it or are victims of it, and where school officials and other authorities act to intervene," the report says.

Most attackers had a history of school disciplinary actions, and many had prior contact with law enforcement: Most attackers had a history of receiving school disciplinary actions resulting from a broad range of inappropriate behavior. The most serious of those actions included the attacker being suspended, expelled, or having law enforcement interactions as a result of their behavior at school.

All attackers exhibited concerning behaviors. Most elicited concern from others, and most communicated their intent to attack: The behaviors that elicited concern ranged from a constellation of lower-level concerns to objectively concerning or prohibited behaviors. Most of the attackers communicated a prior threat to their target or communicated their intentions to carry out an attack. In many cases, someone observed a threatening communication or behavior but did not act, either out of fear, not believing the attacker, misjudging the immediacy or location, or believing they had dissuaded the attacker. "Students, school personnel, and family members should be encouraged to report troubling or concerning behaviors to ensure that those in positions of authority can intervene," the report says.