Childhood Clues to What Drove Three Mass Murderers

A common thread is trauma — and an attachment to guns

Jean Campbell
Nov 30, 2020 · 8 min read
Image for post
Image for post
Eric Harris via

Mass murder in the United States has skyrocketed in the last two decades. Shootings with multiple victims are more common than ever — tripling in frequency in the last ten years. The US has, by far, the most mass shooting incidents, with at least one every 64 days.

Omar Mir Seddique Mateen (The Orlando Shooter)

Omar Mateen is known for killing 49 people at the Pulse gay nightclub in Orlando, Florida in 2016. During the attack, 53 people were also wounded. At the time, it was the worst mass shooting carnage the US had ever seen.

His obvious motive was homophobia, but he — like other mass killers — raged against women, authority, and society. He had another important trait in common with the other three murderers profiled here: he loved guns.

Ultimately, he died by gunfire when the police cornered him in the early morning hours. After a three-hour stand-off, Mateen died from eight bullet wounds after officers fired 150 rounds.


Omar Mateen was raised by both parents. His father was an Afghani immigrant who came to the U.S. in the 1980s and settled in New York City. At the age of four, the family relocated to Ft. St. Lucie, Florida — where Omar would spend the rest of his life.

Image for post
Image for post
Omar Mateen. Photo source.

Omar was an aggressive, impulsive child. He attended Mariposa Elementary, where his third-grade grade teacher recorded that he was, “constantly moving, verbally abusive, rude, aggressive…[frequent] talk about violence and sex…hands all over the place — on other children, in his mouth.”

Classmates reported that he was both a bully, and bullied by other kids. He had low social skills, with a tendency to be disrespectful of girls. He acted like he knew more than the other kids, and suffered from a weight problem.

The school interacted mainly with Omar’s father, who dismissed these problems as something his son would grow out of.

The family was described as “All-American” and were considered moderate Muslims. A classmate witnessed Mateen’s father slapping his son in public, so it is likely he experienced physical abuse at home.

Teen Years

In seventh grade, Mateen was removed from the regular classroom and began sheltered classes for “emotionally disabled” children.

In eighth grade, a letter went home in which the teacher explained that Mateen lacked normal ability to “show self-control” and had a poor attitude.

In 1999, Mateen began high school as he neared his 14th birthday. He got into a fight with another student in math class; police were called. He was briefly arrested and detained. The charges of battery and disrupting school were quickly dropped.

Shortly thereafter, he switched to an alternative school called Spectrum.

As a sophomore at his new school, which catered to youth with behavior problems, it didn’t take long for Mateen to become unpopular: he began cheering after the September 11th attacks. On the school bus home, he imitated a crashing plane.

After another fight, Mateen changed schools again — this time trying out St. Lucie West Centennial. He eventually returned to St. Martin County High School, joined the vocational program, and graduated in 2003 — but not before being suspended a total of 48 days for fighting.

Later interviews with school officials indicated that despite frequent intervention, Mateen never responded by changing his behavior for very long. School officials stated this his father “always took his son’s side,” making progress difficult.

Eric Harris (Columbine)

Eric Harris and Dylan Klebold are known as the Columbine shooters. They killed 13 people and injured 25 on April 20, 1999. Both boys shot themselves in the head in the school library.

They had begun plans for the school shooting, with the hope of bombing the school, over a year before.

Both teens were victims of extreme bullying at school, but evidence shows Harris was more often a perpetrator than a victim.


Eric was born on April 9, 1981, into a middle-class family. His mother was a homemaker and caterer who raised two boys, Eric being the younger. His father was a career Air Force officer, so the family moved around every few years.

During the summer of Eric’s 12th year, his father retired and the family moved to Littleton, Colorado.

Kathy and Wayne Harris were considered good parents who provided a warm, stable environment for their sons. Eric played Little League and participated in Boy Scouts. He was a successful student, interested in video games. When they moved to Colorado, he became fast friends with Dylan.

Teen Years

Eric met Dylan Klebold six years before they would massacre classmates and terrorize their high school. Both boys attended Columbine, and both were highly intelligent. Eric, however, was the better student.

He also knew how to tell adults just what they wanted to hear.

On the surface, Eric was another teen boy into video games who studied hard and participated in extracurricular activities such as the school computer club. Later, investigators would discover Eric’s hidden side.

The teen was consumed with a superiority complex and intense hatred of everyone except, perhaps, his best friend.

Many of his teachers, however, had noticed his morbid, depressed, and violent side. Some had voiced concerns, but the school took no action. The Harris’s stated they had not been informed by teachers that Eric was having problems.

The mother of one of his friends (Brooks Brown) also took official action against Eric Harris, who she felt was extremely dangerous. She went so far as to contact the Jefferson County Sheriff’s Office, after seeing online materials posted by Harris.

In late 1997, a year and a half before the Columbine massacre, the Sheriff’s Department drafted an affidavit and got a search warrant. But they never pursued the complaint.

For anyone besides his teachers, there was nothing especially remarkable about Eric’s life before the shooting, except for an incident in January 1998 in which he and Dylan were arrested.

Criminal tendencies

The two boys broke into a van and stole tools, for which they were charged with felony trespassing.

Eric, being a nice (white) boy with no prior record, got light punishment. He was a model offender, and his juvenile justice caseworker eventually cleared his record after Eric wrote his required apology letter and jumped through a few criminal justice hoops.

Eric’s website, too, revealed an obsession with violence. On it he stated, “God, I can’t wait to kill you people.”

A few days before the shooting, Eric was rejected by the Marine Corps due to his history of taking Luvox, an anti-depressant also used to treat Obsessive-Compulsive Disorder.

The eminent psychologist Robert Hare noted that Eric Harris was a classic psychopath, and the FBI agreed. Eric considered himself a god and found other people highly annoying. (Klebold, on the other hand, was motivated primarily by vengeance.)

Eric did not have problems with impulse control, as the Columbine attack was meticulously planned. He simply wanted to show the world he was a superior being.

Stephen Paddock (The Las Vegas Shooter)

Image for post
Image for post
Stephen Paddock. Photo source

On October 1, 2017, at 10:05 pm, a man began firing into a crowded outdoor concert in the heart of Las Vegas. The bullets flew for 10 minutes, fired from several modified, semi-automatic AR-15-style rifles.

Stephen Paddock spent over 1,000 rounds of ammunition. He killed 61 people and injured 867 concert-goers (411 by gunfire).

At 10:15 the barrage of bullets came to an abrupt stop. Paddock had ended his life with a gunshot to the brain.


Paddock was raised in Tucson and Los Angeles in a family of four boys. He was the oldest child, always self-sufficient and self-disciplined.

His father, Benjamin, was by far the most flamboyant family member.

Benjamin Paddock was a career criminal who escaped after robbing a Phoenix, AZ bank in 1960. His father was imprisoned in 1969, escaped, and spent time on the FBI’s Most Wanted List. Ben had virtually nothing to do with his sons.

His father was also, according to the FBI, a psychopath.

Stephen’s mom, Irene Hudson, raised four boys while working full time. The family had few resources, as she remained single. His brothers have called Stephen both the least violent and the “most boring” family member.

Irene served them powdered milk because real milk cost too much, and never talked to them about their father.

Teen Years

In 1970, Stephen played on his high school tennis team. By then, his family was firmly established in Los Angeles. He focused on earning money, with the belief that if he set his mind to it, he could become rich one day.

According to classmates, Stephen was well-behaved on the surface. But at least one peer reported him cheating, and laughing it off. He wanted to win, at any cost.

He graduated high school on time in 1971.

Very little else is known about Stephen Paddock’s early years, and those who knew him back in the day described him as ordinary. Some reported that he had a superiority streak, was impatient and was highly competitive.

There is evidence that Stephen Paddock lived a double life leading up to the shootings. He may have been wearing a mask of normalcy his whole life.

There is debate about whether Paddock was a psychopath, and his early years (what little is known) shed no new light. His detailed planning of how to kill as many people as possible does reveal, in the words of one analyst, a “reptilian brain.”

Anecdotal and scientific evidence

In 2018, the US Department of Justice funded a large study to better understand mass shooters. Their findings? Mass shooters share four definitive traits.

All mass shooters have lived through a significant childhood trauma. They all “snap” after going through a personal crisis — or are obsessed with a particular recent event in which they felt wronged.

They all use a map or “script” that validates their feelings and helps them cope. The fourth common factor should surprise no one: access to guns.

In these cases — Mateen, Harris, and Paddock — there are more differences than commonalities. People tried to intervene with Harris and Mateen, but never with Paddock. Both Harris and Paddock performed well in life, but Mateen did not.

Mateen seemed destined for self-destruction, whereas Harris only appeared troubled to a few incisive observes. Paddock gave no clue that anything was wrong in his 64 years.

Three cases out of hundreds don’t answer the question about why mass murder happens. Mass murder is nearly impossible to prevent, it seems, because its agents often fly quietly under the radar.

The True Crime Edition

All you need for your true crime fix

Sign up for The True Crime Edition Newsletter

By The True Crime Edition

Your true crime fix in one place. Take a look

By signing up, you will create a Medium account if you don’t already have one. Review our Privacy Policy for more information about our privacy practices.

Check your inbox
Medium sent you an email at to complete your subscription.

Jean Campbell

Written by

Writer in true crime, humor and poetry. For more, check out my web page at

The True Crime Edition

A publication that delves into fascinating cases, the psychology behind criminals and the history of finding them.

Jean Campbell

Written by

Writer in true crime, humor and poetry. For more, check out my web page at

The True Crime Edition

A publication that delves into fascinating cases, the psychology behind criminals and the history of finding them.

Medium is an open platform where 170 million readers come to find insightful and dynamic thinking. Here, expert and undiscovered voices alike dive into the heart of any topic and bring new ideas to the surface. Learn more

Follow the writers, publications, and topics that matter to you, and you’ll see them on your homepage and in your inbox. Explore

If you have a story to tell, knowledge to share, or a perspective to offer — welcome home. It’s easy and free to post your thinking on any topic. Write on Medium

Get the Medium app

A button that says 'Download on the App Store', and if clicked it will lead you to the iOS App store
A button that says 'Get it on, Google Play', and if clicked it will lead you to the Google Play store