Menus Subscribe Search
hope-columbine

The HOPE Columbine Memorial Library that replaced the library where most of the massacre took place. (PHOTO: BIGMAC/WIKIMEDIA COMMONS)

Inside the Mind of a Mass Killer

• July 29, 2013 • 4:00 AM

The HOPE Columbine Memorial Library that replaced the library where most of the massacre took place. (PHOTO: BIGMAC/WIKIMEDIA COMMONS)

A new analysis of the writings of mass shooters finds a common strain of paranoia.

In trying to understand the actions of a mass murderer, our instinct is to grasp blindly for answers, settling on one that feels right. Setting aside the debate over access to guns, this often comes down to a lay diagnosis that the shooter was probably a psychopath—cold, unfeeling, heartless.

A new analysis of the writings of three mass killers and one would-be mass killer, comes to a very different conclusion. A trio of University of British Columbia psychologists led by Donald Dutton report the gunmen appear to have suffered from an intense form of paranoia.

Far from being cool or detached, these young men were enraged, their delusions of persecution becoming ever more intense and intolerable.

“The paranoid individual is obsessed with revenge and justifies the revenge as payback for a perceived injustice. (Such people are) thin-skinned or hypersensitive to perceived slights.”

“They become and remain fixated and obsessed with rejection by what they see as an elite in-group, whom they see as having unfairly achieved success,” Dutton and his colleagues write in a compelling paper just published in the journal Aggression and Violent Behavior. “Instead of transcending the rejection, they formulate plans to annihilate the transgressors, which they justify as vengeance for the transgressions made against them.”

The researchers analyzed the writings of Eric Harris, who (along with friend Dylan Klebold) killed 13 of his fellow students at Columbine High School in 1999; Seung Hui Cho, who killed 32 people at Virginia Tech in 2007; Kimveer Gill, who shot 20 people, killing one, at Dawson College in Montreal in 2006; and Anders Breivik, who killed 82 people at a youth camp in Norway in 2011 (plus another seven in a bomb blast outside the Prime Minister’s office).

They looked at the perpetrators’ diaries or blog entries in the weeks leading up to the shooting, as well as a manifesto Breivik circulated in a mass email in an attempt to explain himself. Aside from Breivik, whose paranoia found expression in socio-political terms, they expressed a surprisingly similar worldview.

“A central theme that runs through these diaries is one of feeling rejected, dismissed, disrespected and devalued by an in-group invariably depicted as “jocks and preppies,” and of wanting vengeance for this maltreatment,” Dutton and his colleagues write. “The in-group is despised for being superficial and for getting unwanted status.”

There is no shortage of examples of this kind of thinking. This is from Harris’ diary:

Everyone is making fun of me because of how I look, how fucking weak I am, and shit, well I will get you all back, ultimate fucking revenge here. You people could have shown more respect, treated me better, asked for more knowledge or guidance more, treated me more like a senior, and maybe I wouldn’t have been so ready to tear your fucking heads off. … Same thing with all those rich snotty toadies at my school. Fuckers think they are higher than me and everyone else with all their $ just because they were born into it?

Here is an online posting by Gill, translated from the French:

If people were making your life a living hell, wouldn’t you be hurt emotionally? How come no one ever talks about those mother fucking jocks and preps whose fault it is. Oh no. Heaven forbid. We can’t possibly say that. Why does society applaud jocks? I do not understand. They are the worst kind of people on earth. And the preps are no better. They think they’re better than others, but they’re not.

Finally, here’s Virginia Tech shooter Seung Hui Cho, apparently addressing the sort of privileged student he despises:

Your Mercedes wasn’t enough? Your golden necklaces weren’t enough? Your trust fund wasn’t enough? Your vodka and cognac weren’t enough? All your debaucheries weren’t enough?

“The paranoid individual is obsessed with revenge and justifies the revenge as payback for a perceived injustice,” the researchers write. “(Such people are) thin-skinned or hypersensitive to perceived slights (and they) have closed information-processing systems that preclude corrective information which is inconsistent with their world view from being received.”

Breivik, the oldest of this group (he was 32 at the time of the killings; Harris was 18, Cho 23, and Hill 25), perceived a different enemy: Muslims. His paranoia “appeared to have worsened when he was past college age,” the researchers write. “Otherwise, his school peers, rather than a politically derived target, may have been selected.”

“He believed that slaughtering a group of teenagers would make him Grand Master Knight Commander, deputized by a secret society to lead the forces of Christendom in a battle for the future of mankind,” they add. “He had military uniforms made to reflect his future status.”

Overall, this analysis suggests many of the media’s cliches regarding mass killers appear to be wrong. They were bullied? “This group greatly exaggerates the negativity of their treatment, as reported by third-party school peers,” the researchers note, adding that their writings contain few references to specific experiences of being a bullying victim.

Perhaps the problem is too few mental health services? Well, three of the four men examined here had been assessed by psychiatrists, none of whom picked up on the deep nature of their disturbances.

That said, one popular conception about these men is clearly correct.

“There were differing levels of social isolation for Cho, Gill, Breivik and Harris,” the researchers write. “Cho had extreme social anxiety, isolated himself and showed social incompetence. Gill and Harris had some friends, but clearly pictured themselves as marginalized. “All were described as loners.”

Tom Jacobs
Staff writer Tom Jacobs is a veteran journalist with more than 20 years experience at daily newspapers. He has served as a staff writer for The Los Angeles Daily News and the Santa Barbara News-Press. His work has also appeared in The Los Angeles Times, Chicago Tribune, and Ventura County Star.

More From Tom Jacobs

A weekly roundup of the best of Pacific Standard and PSmag.com, delivered straight to your inbox.

Recent Posts

July 31 • 8:00 AM

Should Athletes Train Their Memories?

Sure, but it probably won’t help.


July 31 • 6:00 AM

Universal Basic Income: Something We Can All Agree on?

According to Almaz Zelleke, it’s not a crazy thought.


July 31 • 4:00 AM

Medical Dramas Produce Misinformed, Fatalistic Viewers

New research suggests TV doctor dramas leave viewers with skewed impressions of important health-related topics.


July 30 • 4:00 PM

Still the World’s Top Military Spender

Although declining in real terms, the United States’ military budget remains substantial and a huge drain on our public resources.



July 30 • 2:04 PM

The Rise of the Nuisance Flood

Minor floods are afflicting parts of Maryland nearly 10 times more often than was the case in the 1960s.


July 30 • 2:00 PM

The (Mostly Awful) Things You Learn After Investigating Unpaid Internships for a Year

Though the intern economy remains opaque, dialogue about the role of interns in the labor force—and protections they deserve—is beginning to take shape.


July 30 • 12:00 PM

Why Coffee Shortages Won’t Change the Price of Your Frappuccino

You’re so loyal to Starbucks—and the company knows it—that your daily serving of caffeine is already marked up beyond the reach of any fluctuations in supply.



July 30 • 10:00 AM

Having Difficult Conversations With Your Children

Why it’s necessary, and how to do it.


July 30 • 8:00 AM

How to Make a Convincing Sci-Fi Movie on a Tight Budget

Coherence is a good movie, and its initial shoot cost about the same amount of money as a used Prius.


July 30 • 6:00 AM

Are You Really as Happy as You Say You Are?

Researchers find a universal positivity bias in the way we talk, tweet, and write.


July 30 • 4:00 AM

The Declining Wage Gap for Gay Men

New research finds gay men in America are rapidly catching up with straight married men in terms of wages.


July 30 • 2:00 AM

LeBron James Migration: Big Chef Seeking Small Pond

The King’s return to Cleveland is a symbol for the dramatic shift in domestic as well as international migration.


July 29 • 4:00 PM

Are Children Seeking Refuge Turning More Americans Against Undocumented Immigrants?

A look at Pew Research Center survey data collected in February and July of this year.


July 29 • 2:00 PM

Under Water: The EPA’s Ongoing Struggle to Combat Pollution

Frustration and inaction color efforts to enforce the Clean Water Act.


July 29 • 12:40 PM

America’s Streams Are Awash With Pesticides Banned in Europe

You may have never heard of clothianidin, but it’s probably in your local river.


July 29 • 12:00 PM

Mining Your Genetic Data for Profit: The Dark Side of Biobanking

One woman’s personal story raises deep questions about the stark limits of current controls in a nascent industry at the very edge of the frontier of humans and technology.


July 29 • 11:23 AM

Where Should You Go to College?


July 29 • 10:29 AM

How Textbooks Have Changed the Face of War

War is more personal, less glorious, and more hellish in modern textbooks than in the past. But there’s still room for improvement.


July 29 • 10:00 AM

The Monolingual American: Why Are Those Outside of the U.S. Encouraging It?

If you are an American trying to learn German in a large German town or city, you will mostly hear English in return, even when you give sprechen your best shot.


July 29 • 8:00 AM

The Elusive Link Between Casinos and Crime

With a study of the impact of Philadelphia’s SugarHouse Casino, a heated debate gets fresh ammunition.


July 29 • 6:00 AM

What Are the Benefits of Locking Yourself in a Tank and Floating in Room-Temperature Saltwater?

After three sessions in an isolation tank, the answer’s still not quite clear.


July 29 • 4:00 AM

Harry Potter and the Battle Against Bigotry

Kids who identify with the hero of J.K. Rowling’s popular fantasy novels hold more open-minded attitudes toward immigrants and gays.


July 29 • 2:00 AM

Geographic Scale and Talent Migration: Washington, D.C.’s New Silver Line

Around the country, suburbs are fighting with the urban core over jobs and employees.


Follow us


Subscribe Now

The Rise of the Nuisance Flood

Minor floods are afflicting parts of Maryland nearly 10 times more often than was the case in the 1960s.

America’s Streams Are Awash With Pesticides Banned in Europe

You may have never heard of clothianidin, but it's probably in your local river.

How Textbooks Have Changed the Face of War

War is more personal, less glorious, and more hellish in modern textbooks than in the past. But there’s still room for improvement.

NASA Could Build Entire Spacecrafts in Space Using 3-D Printers

This year NASA will experiment with 3-D printing small objects in space. That could mark the beginning of a gravity-free manufacturing revolution.

The Most Popular Ways to Share Good and Bad Personal News

Researchers rank the popularity of all of the different methods we have for telling people about our lives, from Facebook to face-to-face.

The Big One

One in two full-time American fast-food workers' families are enrolled in public assistance programs, at a cost of $7 billion per year. July/August 2014

Copyright © 2014 by Pacific Standard and The Miller-McCune Center for Research, Media, and Public Policy. All Rights Reserved.