Trauma is one of those words that’s used so often, it’s hard to know exactly what it means. Nick Haslam, a professor of psychology at the University of Melbourne, Australia, argues that the modern tendency of describing every misfortune as trauma, from reading or watching something offensive without a trigger warning to marital infidelity, is perhaps the most egregious example of “concept creep” in psychology.1 The elasticity of the term, he adds, diminishes the experiences of people who have experienced true trauma.
Perpetrator A’s childhood was plenty traumatic. His terrible and tragic circumstances feel qualitatively different from any experience that is merely upsetting or distressing. So, is Perpetrator A traumatized? It seems likely. But to really answer that question, we have to take a step back. Because trauma is an outcome. The input is childhood adversity, a broad concept that captures a wide range of circumstances or events that pose a serious threat to a child’s physical or psychological well-being.
Common examples of childhood adversity include child abuse and neglect and family or community violence, but bullying, serious accidents or injuries, and discrimination also qualify. The majority of youth who experience some adversity don’t demonstrate any serious clinical symptoms. Of those who do, there are various trajectories, but the majority will recover. For some children, though, these experiences have serious consequences, especially when they occur early in life, are chronic and/or severe, or accumulate over time. Adversity does not predestine children to poor outcomes, but research shows it can become biologically embedded during sensitive periods of development, meaning that without appropriate intervention, it can lead to lifelong physical and mental health problems.
These significant childhood adversities are sometimes referred to as ACEs, for adverse childhood experiences. The ACEs concept originated from a seminal study by Kaiser Permanente Health Care.2 Between 1995 and 1997, researchers asked 13,500 adults in California about childhood adversities in seven categories: experiencing physical abuse, sexual abuse, and/or emotional abuse; having a mother who was treated violently; living with someone who was mentally ill; living with someone who abused alcohol or drugs; and incarceration of a member of the household. They found that the more ACEs an adult reported from their childhood, the worse their physical and mental health outcome.
Subsequent studies have expanded the definition of ACEs to include parental divorce and separation and homelessness, but no matter how you slice it, ACEs are linked to increased risk of heart disease, diabetes, substance misuse, and other negative outcomes. Those with the most ACEs, like four or more, also tend to have higher rates of mental illness. It’s impossible to say that ACEs cause these negative outcomes—some children are more likely to be abused because they have disabilities or because they are being raised by parents with their own mental health problems that lead to abuse, masking the exact role of the trauma in this complex equation. However, the research overwhelmingly shows that ACEs do matter.
ACEs are surprisingly common. According to the Centers for Disease Control and Prevention, about two-thirds of adults report having experienced at least one type of ACEs as a child, and around 13 percent of people, such as Perpetrator A, have experienced four or more.
Which brings us back to trauma. Trauma is one possible outcome of exposure to adversity. According to the National Child Traumatic Stress Network, the American Psychological Association says trauma is “an emotional response to a terrible event,” something “frightening, dangerous, or violent” that “poses a threat to someone’s life or bodily integrity.”
Certain types of childhood adversity are especially likely to cause trauma reactions in children, such as child abuse, the sudden or violent loss of a family member, or refugee and war experience. Witnessing a loved one experience violence, such as domestic assault, can also cause a trauma reaction. Children exposed to extremes of violence and abuse can develop PTSD, meaning they can feel stressed or frightened even when they are no longer in danger, and their experience of violence is played back to them in flashbacks and night terrors.
Our bodies are hardwired to react to adversity. When we experience it, the stress hormones adrenaline and cortisol flood our bodies, dialing up our heart rates and energy levels. Once a threat subsides, our bodies quickly return to normal. But when stressors are always present, and we constantly feel under attack, high alert can itself become normal, and the experiences of violence and abuse will remain in the cells of our bodies like an encoded shock waiting to be unleashed.
When your stress response is routinely activated, it is more likely to be activated in the future. Everyone responds differently, but a stress response can look aggressive, agitated, blunted, or withdrawn. These responses, if not understood, can push people away—teachers, neighbors, peers. When our fight-or-flight reaction stays turned on, it wears down the body and brain over time. This is called “toxic stress.” Toxic stress changes how the brain makes connections and processes information, and because of this, children exposed to extreme, long-lasting adversity can have a warped view of the world. For them, the world is a scary, unpredictable, and unsafe place, and the adults in their lives cannot be trusted to care for and protect them.3 It’s enough to make people retreat inward into extreme isolation or lash out violently like Perpetrator A.
In 1989, psychologist Cathy Spatz Widom conducted a pioneering study on nine hundred individuals with experience of abuse prior to the age of eleven. She found a clear link between trauma and violent criminal behavior, showing that abused children were at a greater risk of being arrested later in life.4 A later, larger study of more than one hundred thousand students in sixth, ninth, and twelfth grade found that each type of childhood trauma increased the risk of both violence against others (delinquency, bullying, physical fighting, dating violence, and weapon carrying on school property) and violence against oneself (self-mutilation, suicidal ideation, and suicide attempts).5
Other studies show that girls who experienced childhood trauma were more likely to have internally focused problems such as depression and anxiety, whereas traumatized boys were more likely to project their feelings outward, through aggression, hostility, and delinquency.6 Childhood sexual abuse, physical abuse, emotional abuse, and neglect are all also strongly associated with suicidal thinking and suicide attempts in teenage boys and girls alike.7
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For many mass shooters, an unpredictable and chaotic upbringing is the first step on their pathway to violence. In our database, we examined childhood trauma histories using publicly available records and sources. For many perpetrators, this was difficult, because little information was out there about their childhoods. For the 60 percent of shooters about whose childhoods we could find enough information, we found significant childhood trauma in over half the cases, or 55 percent; in the general population, that number was more like 15 percent.
Two profiles ended up emerging: those with childhood trauma and those with adult trauma. The shooters who experienced childhood trauma were most likely to be school shooters, college and university shooters, or place-of-worship shooters. In fact, nearly 70 percent of school mass shooters had a known history of childhood trauma. Perpetrators with a history of childhood trauma killed significantly more people than shooters without trauma (an average of ten versus six people). They were more likely to be raised by a single parent and more likely to have been bullied in school. Traumatized perpetrators were also more likely than other mass shooters to have a mental health history, have a problem with alcohol, and have a history of being suicidal. They were also more likely to tell people about their plans to commit a mass shooting before they did it.
Several mass shooters were abused by their mothers in childhood. In 1993, a nineteen-year-old shot and killed four people at a Chuck E Cheese restaurant. The perpetrator, a former employee, was apparently frustrated about being fired five months before and had sought revenge by committing the attack. He fled the scene of the shooting with stolen money and restaurant item
s. What is less well-known is that he was raised by a mother who had untreated bipolar disorder. She was physically, mentally, and sexually abusive to him throughout his childhood. Also, when he was fifteen, he walked in on his stepfather raping his sister.
Being abused by a father figure was even more common for mass shooters. The San Bernardino shooter, who (along with his wife) left fourteen people dead at a Department of Public Health Christmas party in 2015, was regularly beaten by his violent, alcoholic father, a man who had severe mental illness. The perpetrator and his siblings had to regularly protect their mother from their father’s abuse.
Several other perpetrators had a parent die during their childhood. The twenty-one-year-old who killed four people by firing from the balcony of a motel in 1975 lost his father to suicide when he was thirteen. The perpetrator of a 2000 shooting spree at a car wash in Texas witnessed his father murder his mother when he was eight years old. Afterward, he developed a speech impairment that lasted through adulthood; his lawyer described him as “the worst stutterer I’ve ever seen.” The 2018 Pittsburgh Tree of Life synagogue shooter’s father died by suicide after being charged with attempted rape when the shooter was just seven.
A few mass shooters spent their childhoods in war-torn countries and came to the United States as refugees. The perpetrator who killed six people on a hunting trip in Wisconsin in 2004 had escaped with his family from the Laotian Civil War, known as the “Secret War in Laos” in the United States. The perpetrator recalled seeing dead children, and his mother reports that the family slept in the jungle, walked until their feet bled, and were afraid of wild animals. The perpetrator of the 2007 shooting at the Trolley Square mall, in Salt Lake City, Utah, was a refugee from the brutal Bosnian War, where he witnessed the murders of women and children, saw the sites of mass graves, and lived in the forest with no food, surviving on wild mushrooms. His brother and sister both died during the war.
Mass shooters often experienced more than one form of trauma throughout their lives, which sometimes could be traced generations back. For example, the perpetrator who killed four people at Lindhurst High School in California in 1992 came from a family with an “incredible amount of trauma,” according to the psychiatrist who testified at his trial. The shooter’s mother was sexually molested by several family members, his uncle was in prison for murdering three people, his grandmother had died by suicide, and his father had left the family when the perpetrator was a child. The perpetrator had chronic, permanent brain damage, possibly resulting from the spinal meningitis he contracted as a baby, which impacted his logical reasoning. At the age of sixteen, he was molested by one of his high school teachers on three occasions. He became obsessed with the incident, and his IQ dropped from a 95 to 84 the year after the abuse.
Mass shooters without a history of childhood trauma more commonly experienced significant trauma as an adult. They were more likely to commit mass shootings at restaurants, retail establishments, workplaces, and other public locations than at schools or colleges, which equally implies that their will to murder came later in life. Eleven perpetrators had a parent die prior to their crime. A number of other mass shooters lost a baby during childbirth, including the man who murdered five schoolgirls in an Amish schoolhouse in 1993, who had recently experienced the death of his infant twenty minutes after she was born; and the fifty-five-year-old gunman who killed five at Milwaukee’s Molson Coors brewery in 2020, who lost a daughter in 2009 after she was born prematurely.
Veterans represent less than 8 percent of the total U.S. adult population, but 27 percent of mass shooters spent time in the military prior to their crimes. Several of them experienced traumatic events while on active duty. A Chicago man who shot and killed two people in an auto parts store in 1988 and then fatally wounded a police officer and a custodian at a nearby school was deeply troubled by his experiences as an army combat infantryman in the Vietnam War. The shooter who killed five travelers at the Fort Lauderdale airport in 2017 had watched two of his friends die in a bomb explosion when he served in Iraq. And the perpetrator of the 2018 shooting at the Borderline Bar and Grill in Thousand Oaks, California, which killed thirteen people, was diagnosed with PTSD after serving in Afghanistan as a marine. He witnessed people dying by IEDs, and many people he knew from the service had died by suicide.
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Trauma feels like an overwhelming problem to solve. It often goes back generations, and the children may not even recognize what’s happening when trauma is their normal. Perhaps the best example of this was in our interviews with Perpetrator B, the school shooter. Despite the abuse he had endured as a child, he was still somewhat protective of his family:
Tell us about your mother; what was she like?
Very loving, kind, and smart. She loved kids and loved being a mother. She was patient and encouraging as well. Faithful wife.
Tell us about your father; what was he like?
He could be strict but had good intentions.
How would you describe your childhood?
It was generally happy, but there were some scary and confusing incidents.
What were the scary and confusing incidents?
My father showed me pornography as a young child, and it disgusted me. My father would sometimes hit or grab my mother.
How often was there violence in your house? Were you afraid as a child?
Violence was not an everyday thing in our house, but more like several times a year. Yes, at times I was afraid as a child. There were good times, too. My father really did love us.
What was it like when you developed mental illness? How old were you?
I started to suffer from some depression during my childhood, although it was not diagnosed at the time, nor did I realize it. I was probably around six or seven. Around age fifteen, I began to suffer from anxiety, and then at seventeen, I developed severe depression and paranoia and suicidal thoughts.
A child who has been abused; who is shy and detached, or impulsive and unable to read others’ cues; who elicits certain behaviors and treatment from peers and adults; who has endured trauma—such a child may have trouble making friends because he drives other children away. He may try the patience of adults. How do we as teachers, parents, doctors, and neighbors step in to help these children? How do we identify kids going through trauma, and is it possible to intervene to prevent the negative lifelong impact?
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We interviewed several people who knew before a mass shooter’s crime that they had experienced trauma in childhood but were unsure how to intervene because they lacked training or time or they didn’t see it as their role. For example, we spoke to a current college professor who was the former preschool teacher of a mass shooter in the database. We found her name from previous media coverage about the shooting and reached out to her through her university email address. She quickly agreed, and we met over Zoom after canceling our flights to go see her in person.
The professor was previously a special education preschool teacher in a public school, working with about ten students at a time, and the perpetrator was one of her students when he was four years old. She describes him fondly as “withdrawn, quiet, shy, and very sweet.” She continues: “He would hide under his mom’s skirt. He didn’t like playing with other children, and there was a sadness about him. He had some speech and language delays; I think English was his second language.”
The perpetrator’s mom would always drop him off at preschool each morning, so the professor got to know her pretty well. She remembers one morning when the mother came to the school with the perpetrator and his younger brother; the mother was crying and visibly upset. The professor is calm as she recalls the moment. “Her husband had held a knife to her throat and threatened to kill her and the two boys. I suggested that she go to a nearby shelter for battered women.” The professor is quiet for a moment.
“Did she go?” Jill asks.
“She went. I think she actually ended up staying there for a few months, b
ut she eventually went back to him.”
Twenty years later, the professor was waiting in an airport, passively watching CNN on a television, when she saw that there’d been a horrific incident at the college where she worked. Someone had gone on a shooting spree, killing six people.
“He even sprayed bullets into a room of the library where students and staff were crouching. Can you imagine the horror?” She describes the moment she made the connection: “I was back at home a day or so later when the news released his name and his picture. I recognized him immediately. I was in shock. He was so quiet. So sweet-tempered. He was adorable. He wouldn’t hurt a fly.”
With time to reflect, the professor has become more convinced that the schools failed him—and that perhaps she did, too. “I never checked back in with his mom to see how she was doing. He needed a social worker to follow up. The mother did, too. The school needed to really help that family in an aggressive way. That moment was so critical—and she reached out to the school for help. To me. She was crying out for help, and we sent her away. I had no training in how to deal with that situation.”
“Was there a reporting system? Did you document it anywhere?” Jill wonders.
She shakes her head, “No. I didn’t report it to anyone.” She feels the weight of the missed opportunity. “The supports are out there, but they are all in their different silos. Yes, the system is broken. But part of me thinks this is simple. Why wasn’t this documented? We need one person to gather this information about our kids. One person to keep track of which kids are experiencing toxic stress, so they don’t keep falling through the cracks like this. Someone has to be the one to step in.”
The Violence Project Page 5