A 20-year-old’s perplexing place in the catalog of American gunmen

In the months after an isolated, deeply troubled 20-year-old took his mother’s AR-style rifle and opened fire inside Sandy Hook Elementary, gun sales in America exploded, partly fueled by the threat of a fresh ban on the assault weapons that would become the firearm of choice for some of the country’s most infamous killers.

Millions of Americans rushed to stock up, and among 2013′s gun buyers, investigators would later learn, was a man in western Pennsylvania whose son also attended elementary school. He purchased an AR-style rifle that fired 5.56mm rounds.

A decade later, his son - also isolated, troubled and 20 years old - shouldered that same rifle atop a sloped roof in Butler, Pa., and, according to authorities, fired it eight times in an apparent attempt to assassinate former president Donald Trump.

Thomas Matthew Crooks, shot and killed seconds later, remains enigmatic. A registered Republican who’d once given a $15 donation to a progressive group, he was, said people who knew him, not overtly political or ideological. He did well in school, drew little attention in his middle-class, Bethel Park neighborhood. He didn’t leave behind a significant online presence or manifesto spelling out his motivation. Why he pulled the trigger, investigators still don’t know or, at least, have yet to say publicly.

Where he fits into the ever-expanding catalog of notorious American gunmen could take years to understand, according to experts and historians. He’s hard to categorize, in part because his still-evolving portrait evokes the profile of a mass shooter, at least one of whom he researched. But Crooks wasn’t a mass shooter, instead becoming what some historians believe to be the youngest person to make an attempt on the life of a current or past president.

It’s important for investigators to understand what leads to any killing, but it’s essential in this case, at this moment, when some fear the country’s political fissures could lead to more bloodshed, said Jeffrey A. Engel, founding director of the Center for Presidential History at Southern Methodist University.

“If this is an individual who was like a school shooter, disturbed and angry, and found this as a way to lash out, that’s a terrible, terrible social problem we need to deal with, but it’s not a question of our democracy,” Engel said. “It’s important that we know whether or not we need to worry about political violence, more than any other violence.”

Three decades ago, the U.S. Secret Service set out to analyze 83 actual or would-be assassins who had acted between 1949 and 1996, eventually publishing a report intended to help law enforcement better understand, and thwart, these attacks.

By study’s end, the researchers had come to a stark conclusion: “There are no accurate - or useful - descriptive, demographic, or psychological ‘profiles’ of American assassins, attackers, and near-lethal approachers.”

Crooks conforms with some of the report’s broader trends: 86 percent were men, 77 percent White; more than half were single, and three in five had no children; most attempts were on presidents, members of Congress or other public figures being protected by the Secret Service.

In other ways, Crooks was anomalous. He was younger than the vast majority, few of whom were students at the time. Just 30 percent used rifles or shotguns, and only one in four traveled elsewhere in their state, or one beside it, in pursuit of their target. There’s little evidence, so far, that Crooks had a “history of resentments or grievances against others,” as 97 percent of those studied did.

And then there are the mass killers Crooks conjures. At a briefing with lawmakers, federal officials shared that Crooks had researched Oxford High shooter Ethan Crumbley as well as his mother and father. Earlier this year, James and Jennifer Crumbley became the first parents of a mass shooter ever convicted of homicide. In a rampage that ended the lives of four schoolmates in 2021, Crumbley, like Crooks, used a firearm that had been purchased by his father.

Crooks parallels the Sandy Hook Elementary shooter, Adam Lanza, in several obvious ways. Besides their ages, both were gaunt and withdrawn, with limited social circles. Both grew up in homes stocked with firearms and had a clear interest in them: Lanza, who aspired to become a Marine, studied guns and fired them with his mother at a shooting range; Crooks, who, investigators and reporters have learned, belonged to a shooting club and died in a T-shirt from a popular YouTube channel dedicated to guns, had tried out for his high school rifle team but didn’t make it because he was a poor marksman. Both 20-year-olds showed signs of rising distress - Crooks researched major depressive disorder on his phone, lawmakers were told - before their violent acts. And Lanza, too, committed his assault with a parent’s semiautomatic rifle.

But the similarities end there, said Peter Langman, a psychologist and the author of “Warning Signs: Identifying School Shooters Before They Strike.” With crude explosive devices packed into his car, Crooks traveled to a rally an hour from his home and took aim at a 78-year-old former president, grazing him, killing firefighter Corey Comperatore and gravely wounding two other spectators. In Newtown, Conn., Lanza killed his mother before returning to a school he’d once attended and gunning down six staff members and 20 first-graders.

Their personal lives diverge as well. When Langman assesses young shooters, he consistently finds that they faltered in key “life domains”: education, employment, intimacy, family and social network.

“If you look at Lanza,” Langman said, “he was failing in, essentially, all five of those domains.”

Lanza, who was diagnosed with Asperger’s syndrome, struggled to function in classes, instead attending home school through much of his teens. He suffered from obsessive-compulsive disorder and was especially sensitive to light and sound. He stopped speaking to his father two years before the shooting and communicated with his mother, with whom he lived, through email. He was obsessed with death, compiling a detailed spreadsheet of 400 people who’d committed various acts of violence.

Crooks, Langman said, appeared to have been succeeding in several of those life domains.

He worked at a nursing home and, after graduating from community college with an associate’s degree in engineering science, planned to attend Robert Morris University in Pittsburgh this fall. It’s unclear whether he dated or what his relationship was with his parents - both licensed professional counselors - but he still lived with them. Those who knew him said that, at least in high school, he maintained a small but consistent group of friends.

“This is not a case of someone who’s failed in everything and feels like he’s a loser, a nobody, and the only thing he can do with his life is go out in a blaze of glory,” Langman said.

Still, he cautioned, it’s early in the investigation. Langman recalled the case of Omar Mateen, who killed 49 people and wounded 53 others at Pulse nightclub in Florida. A cursory look at Mateen would have suggested that he also led a relatively successful life. He had a wife and child and worked as a security guard.

“People in those situations are not supposed to throw it all away, because it’s too much to live for, but he did,” Langman said. “When you see that, then you have to really look inside the man. Not look at the externals, but look at the internals.”

That look, Langman said, revealed a psychopath.

Mateen beat his wife, she later alleged, and while he did hold a job, he failed in his aspiration to make a career in law enforcement, at least in part because of his preoccupation with violence.

Who Crooks really was has yet to be revealed, but that doesn’t mean it never will. After the Sandy Hook shooting, many people concluded that Lanza had left behind no online footprint.

“It turned out not to be true at all,” Langman said. “He covered his tracks very well.”

So well, in fact, that six hours of audio Lanza recorded wasn’t discovered on YouTube until 2021 - nine years after his death.

And yet, what drove him to such horrific violence remains unknown.

Despite public perception, assassins’ motives can be equally difficult to flesh out.

“When the first crack of the bullet is heard, aimed at a political figure, it’s natural for us to presume, logical even, that this is politically motivated,” said Engel, the presidential historian.

That, he explained, is often not the case.

In 1881, President James Garfield’s killer, Charles J. Guiteau, who was delusional, felt slighted over a job he didn’t get. Nearly a century later, Lynette “Squeaky” Fromme tried to shoot President Gerald Ford, at least in part to win the approval of cult leader Charles Manson.

“I’m still not sure that we have a great grasp of what was motivating Lee Harvey Oswald,” Engel said of President John F. Kennedy’s killer. “And of course, most famously, John Hinckley, who shot at Ronald Reagan, did it basically to impress a girl” - the actress Jodie Foster.

Crooks, it appears, wasn’t only interested in Trump. On his phone, investigators found images of President Biden, Attorney General Merrick Garland and a member of the British royal family. Along with the rally in Butler, Crooks had looked up information on August’s Democratic National Convention in Chicago.

Those disparate inquiries, experts say, suggest that Crooks may have largely been driven by a desire for attention and chose his target out of convenience.

“This is a person likely trying to make headlines, going out in a final act,” said Jillian Peterson, a forensic psychologist and co-founder of the Violence Prevention Project. “This is the thing that they’re going to be seen for.”

Perhaps no school shooter motivated by a quest for fame received more of it than 18-year-old Eric Harris, who, along with a friend, Dylan Klebold, killed 13 people at Columbine High in Colorado in 1999.

“I want to leave a lasting impression on the world,” Harris once wrote. Propelled by intense media coverage of his image, backstory and demented world view, Harris’s persona has inspired dozens of gunmen in the 25 years since, including Lanza.

Over the past decade, public mass shooters have won far less notoriety as their numbers have multiplied. Even some of the deadliest killers - the ones at Robb Elementary in Uvalde, Tex., and the Route 91 Harvest festival in Las Vegas, for example - are not household names.

In a single week, Crooks’s name has appeared in thousands of headlines as his image spread across the globe. Peterson fears that other disillusioned fame-seekers who once would have turned to a different sort of violence may now be emboldened to attempt this kind.

“It has changed the course of the political conversation. It’s having ripple effects. It’s actually changing politics, and potentially the election in some way,” she said. “So, if one 20-year-old kid with an AR-15 can pull that off, that is something that’s scary.”

Peterson also noted there is only one commonality among all isolated, troubled young men who eventually become shooters, and America has struggled to address it since long before Crooks’s father bought that rifle 11 years ago: their access to a gun.

Perry Stein and Devlin Barrett contributed to this report.