FBI Finds Few Red Flags on a Would-Be Assassin

He was interested in chess and coding, and had recently received an associate’s degree in engineering science. High school classmates remembered him as an intelligent student who had few friends, but who never exhibited any glaring red flags. The nursing home where he had a job helping with meals said his work gave its staff no reason for “concern.”

And in an era when other people his age put troves of personal information online, Thomas Matthew Crooks, 20, left few clues about who he was, what he believed, or why he decided to drive to a Trump rally in western Pennsylvania on Saturday and try to assassinate the former president.

On Sunday, federal investigators said a shooter they identified as Crooks had used an AR-15 style rifle purchased by his father to open fire from a rooftop outside the rally where the former president, Donald Trump, was speaking. In a series of new details, FBI officials said they were investigating the incident as a possible case of domestic terrorism, and that the gunman had left behind explosive materials in the vehicle he drove to the event.

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But many other details of Crooks’ life and motives of were still unclear. Federal authorities said he had no apparent history of mental health issues or previous threats, and had not been on the radar of federal law enforcement.

Investigators were scouring his online presence and working to gain access to his phone, but so far had not found indications of strongly held political beliefs. In fact, the clues he left behind were confusing: He was a registered Republican but had also donated to a progressive cause in 2021; his parents were registered as a Democrat and Libertarian.

Crooks was shot and killed by Secret Service agents moments after he began firing, killing a spectator, seriously wounding two others and leaving Trump with an injury to his ear.

Kevin P. Rojek, the FBI official in Pittsburgh who is leading the investigation, said Crooks is believed to have acted alone and that there were no additional public safety concerns.

Attorney General Merrick Garland said that the shooting was “an attack on our democracy” and that federal authorities would use every available resource to investigate the shooter.

Crooks grew up in the relatively affluent suburb of Bethel Park in the South Hills region of Pittsburgh, about an hour’s drive from the site of the rally.

His parents are both licensed counselors, according to Pennsylvania records. His father worked at a local behavioral health provider, according to his LinkedIn profile.

The neighborhood where the family lives is “pretty firmly middle class, maybe upper-middle class,” Dan Grzybek, who represents the area on the county council, said in an interview Sunday.

Grzybek briefly met the gunman’s parents last year when he was canvassing for his run. He did not recall the exact conversation, but he remembered they seemed pleasant and were open to hear his platform.

He said it was not unusual to have families in which different members had different political beliefs.

“You’ve got a large spattering of different backgrounds and ideals, and definitely have a lot of mixed households in Bethel Park,” he said.

Just two months ago, Crooks graduated from the Community College of Allegheny County with an associate degree in engineering science, a school official said.

Crooks had been working as a dietary aide at Bethel Park Skilled Nursing and Rehabilitation Center. Marcie Grimm, the facility’s administrator, said the organization was shocked to learn of his involvement in the shooting, saying that he had “performed his job without concern and his background check was clean.” She declined to discuss further specifics of his employment, saying that center officials were cooperating with law enforcement investigators.

According to a federal law enforcement official, dozens of FBI agents, analysts, evidence technicians from multiple divisions have gathered to work the case. The FBI was trying to break into the gunman’s cellphone with court approval to learn more about his plans and motive. President Joe Biden said Sunday that officials had not identified a motive.

The FBI has not found a manifesto, and Crooks had never been under FBI investigation. The official confirmed that he did not have an unusual online history for a 20-year-old man. He liked to play chess, video games and was learning how to code, according to a review of his online activities.

He did not appear to have a public profile on major social media platforms including Facebook and Instagram. The messaging platform Discord said it had found an account apparently linked to the gunman, but the company said that “it was rarely utilized and we have found no evidence that it was used to plan this incident or discuss his political views.”

Two former classmates who attended Bethel Park High School with the gunman said they had not noticed any obvious warning signs.

One of the classmates, Zach Bradford, said he had taken American history and government classes with him, that Crooks appeared to be “incredibly intelligent” and that his views in high school seemed “slightly right leaning.” Bradford said he remembered a couple of instances in which classmates gave Crooks a hard time, but he was shocked when he heard that Crooks had been identified as the shooter.

“I honestly would’ve never expected this,” he said.

The Bethel Park School District confirmed that Crooks graduated from Bethel Park High School in 2022 and said it was cooperating with law enforcement, but it did not provide any additional details about the gunman’s time as a student.

He was one of 20 students awarded a $500 prize for math and science that year, according to local news reports, and in April 2022 appeared in a video on the school’s Facebook page, perched over a laptop as he explained coding to another student.

An AR-15-type semiautomatic rifle was found next to Crooks’ body. Investigators said Sunday that while the weapon had been purchased by the gunman’s father, they did not know how the gunman took possession of it or whether he had used it without his father’s knowledge. Rojek of the FBI said the gunman’s family was cooperating with the investigation.

Law enforcement officials found materials for two explosive devices in Crooks’ car and believe they have may have found a third at his residence, according to a person with knowledge of the investigation.

On Sunday, a clue emerged as to how Crooks may have trained in the use of firearms. The Clairton Sportsmen’s Club, a wooded facility south of Pittsburgh, that features a 200-yard-rifle range, confirmed that Crooks had been a member.

“The Club is unable to make any additional commentary in relation to this matter in light of pending law enforcement investigations,” the club said in a statement released by its legal counsel, Robert Bootay, expressing sympathy for the family of Corey Comperatore, a spectator who was killed. “Obviously, the Club fully admonishes the senseless act of violence that occurred yesterday. The Club also offers its sincerest condolences to the Comperatore family and extends prayers to all of those injured including the former President.”

Former FBI officials said the bureau’s behavioral analysis unit would try to build out a profile of the gunman to understand his motivations. The FBI, which is running the investigation, will cast a wide net, interviewing friends and family members and searching for clues he might have left online or in a journal.

The gunman did not have a criminal history reflected in Pennsylvania’s public court records. A voter registration record listed Crooks as a registered Republican, though federal campaign finance records show he donated $15 to the Progressive Turnout Project, a liberal voter turnout group, through the Democratic donation platform ActBlue in January 2021.

Law enforcement officers closed down all roads leading toward the home of the suspect’s family in Bethel Park. Numerous relatives did not respond to messages seeking comment.

Grzybek, who lives about a half-mile down the same street as the gunman’s family, said the area was in shock.

“Most people just can’t believe that this has happened in our neighborhood,” he said. “I typically walk my dogs every morning, and the number of people that I’ve seen walking through our street, just driving down and just stopping to take video and pictures, I think is pretty remarkable.”

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