By Harshit | September 27, 2025 | New York City | 8:30 AM EDT
The former high school football player who carried out a deadly mass shooting inside a Manhattan office tower housing the NFL’s headquarters was suffering from chronic traumatic encephalopathy (CTE), the New York City medical examiner confirmed Friday.
Details of the report
Shane Tamura, 27, who killed four people on July 28 before fatally shooting himself, showed “unambiguous diagnostic evidence” of low-stage CTE, according to the examiner’s report. The degenerative brain disease, linked to repeated head trauma, can only be definitively diagnosed after death.
Tamura, a Las Vegas casino worker, had intended to target the NFL’s offices but mistakenly took the wrong elevator, officials said. The victims included a police officer, a security guard, and two office workers. One NFL employee was injured in the lobby but survived.
Authorities recovered a three-page note in Tamura’s wallet, in which he wrote: “Study my brain.” He accused the NFL of prioritizing profits over player safety and concealing the risks of CTE and football-related brain trauma.
Background on CTE
CTE affects areas of the brain that regulate mood and behavior. It has been linked to concussions and repetitive head injuries, often seen in contact sports such as football, hockey, and boxing.
Although Tamura never played professionally, he competed in high school football in Southern California. “Even a low-stage diagnosis of CTE could be responsible for behavioral changes and impulse control problems,” said Dr. Daniel Daneshvar, a Harvard University specialist in brain injury rehabilitation. However, he cautioned against drawing a direct line between the disease and Tamura’s violent actions.
NFL and public response
The NFL issued a statement condemning the attack while acknowledging ongoing research into CTE. “There is no justification for the horrific and senseless acts that took place,” the league said. “As the medical examiner notes, the science around this condition continues to evolve, and the physical and mental manifestations of CTE remain under study.”
The NFL formally admitted in 2016 that football is linked to CTE, after years of denial. Since then, it has paid more than $1.4 billion in concussion-related settlements to retired players.
Tamura’s mental health history
Officials disclosed that Tamura had a history of mental health crises. In 2022, his mother called 911 reporting that her son was threatening suicide and suffered from depression, chronic migraines, and insomnia. In 2023, he was arrested for trespassing at a Las Vegas casino after becoming agitated, though the charge was later dismissed.
Implications
The case reignites concerns over the lasting impacts of head trauma in athletes, even at the amateur level. While researchers stress that CTE alone cannot explain Tamura’s actions, the diagnosis underscores the disease’s potential role in behavioral instability and public safety risks.
As investigators continue examining Tamura’s background, the tragedy adds to the debate over the NFL’s handling of brain injuries and the broader responsibility of sports organizations to protect players from long-term neurological damage.
