In the years before the July 2024 campaign rally shooting in Butler, Pennsylvania, Thomas Crooks became increasingly focused on firearms and precision shooting, according to federal records reviewed by The Post. Crooks later opened fire in what authorities identified as an attempted assassination of President Trump.
Information about Crooks’ growing interest in guns and long-range target practice was contained in documents turned over to Sen. Chuck Grassley, the Iowa Republican who chairs the Senate Judiciary Committee. Grassley is continuing to investigate the first attempt on Trump’s life.
Matthew Crooks, the shooter’s father, told FBI investigators that most of his son’s conversations with him centered on firearms and were generally short.
Matthew said he did not view their mutual interest in guns and shooting as a typical father-son pastime. Instead, he told investigators he believed Thomas had “ulterior motives,” which became apparent “the minute he pulled that trigger,” apparently referring to the attack at the Trump rally.
The Panther Arms A-15 semiautomatic rifle used in the shooting attempt belonged to Matthew, who handed it to his son on the morning of July 13, 2024.
Matthew said he removed the rifle from a locked safe and gave it to Thomas because he believed his son planned to visit a shooting range. He had frequently changed the safe’s combination after noticing Thomas trying to watch as he entered the code.
According to his father, Thomas began developing an interest in guns and target shooting during the coronavirus pandemic.
At the beginning, however, his marksmanship was reportedly poor. Matthew described him as a “terrible” shot.
A summary of Matthew’s FBI interview, conducted the day after the Butler rally attack, said Thomas initially “could not hit the paper” target.
Matthew told investigators that his son spent roughly four or five years practicing before he was consistently able to strike the target.
Thomas also expressed interest in eventually inheriting firearms owned by both his father and grandfather.
Matthew recalled one conversation as particularly unusual, saying Thomas asked whether he would need to complete a background check to purchase his father’s Glock pistol.
In another unsettling episode, Matthew watched security-camera footage of Thomas moving around the family garage while cleaning one of his guns. He said the 20-year-old was waving his arms, speaking rapidly and “not making any sense.”
The incident occurred on July 7, 2024, less than a week before the attempted assassination of Trump at the Pennsylvania rally.
Matthew said Thomas later improved his performance at the range after purchasing a prism sight, allowing him to shoot at greater distances. His son also became “very knowledgeable” about measuring distances and properly zeroing the optic, according to the interview summary.
The sight may have been among the numerous “parts, tools and items to increase the capacity of his rifle” that Thomas purchased on Amazon using the pseudonym “Bob Dole.”
Thomas would often come back from the shooting range showing his father his shot grouping on targets that were 100-plus yards out.
When Matthew questioned Thomas — who was not a hunter — why he was “going out so far,” he told his father he just wanted to see how far he could shoot with rudimentary sights.
On at least one occasion, Thomas even attempted to manufacture a weapon on his own.
Using his 3D printer, Thomas made a Glock-19-style handgun and showed it to his father.
Matthew told investigators he discharged only one round from the 3D-printed weapon, and, fearing the frame would explode, barred Thomas from taking it to the range.
