On July 28, 2025, the tranquil routine of a Manhattan office building was shattered when Shane Devon Tamura, a 27-year-old former high school football player, opened fire at 345 Park Avenue, the headquarters of the National Football League (NFL). By the time the violence ended, four people were dead, one was seriously wounded, and Tamura himself had died by suicide. Now, the New York City Office of the Chief Medical Examiner has confirmed that Tamura suffered from low-stage Chronic Traumatic Encephalopathy (CTE), a degenerative brain disease most commonly linked to repeated head trauma in contact sports like football.
The attack was swift and devastating. According to reports from ABC News and the BBC, Tamura drove cross-country from Las Vegas to New York, armed with an assault-style rifle. Entering the building just after 6:28 p.m., he moved through the lobby with chilling efficiency. Within less than 30 seconds, three people were fatally shot: Aland Etienne, a security guard; Wesley LePatner, a Blackstone executive; and Didarul Islam, an off-duty NYPD officer. Tamura then moved toward the elevator bank, inexplicably allowing a woman to pass unharmed, before heading to the 33rd floor. There, he encountered and killed Julia Hyman, a young employee at Rudin Management, before turning the gun on himself. In total, Tamura fired 47 rounds, reloading once, police said.
In the aftermath, investigators found a three-page note in Tamura’s pocket. In his own words, Tamura wrote, “Study my brain please. I’m sorry.” He blamed the NFL for “concealing the dangers to players’ brains to maximize profits.” The note, and Tamura’s actions, pointed toward a troubled mind grappling with both mental health struggles and a possible neurological disorder.
The medical examiner’s report, released on September 26, 2025, confirmed what Tamura had suspected: “Following a thorough assessment and extensive analysis by our neuropathology experts, OCME has found unambiguous diagnostic evidence of Chronic Traumatic Encephalopathy, also known as CTE, in the brain tissue of the decedent. The findings correspond with the classification of low-stage CTE, according to current consensus criteria,” the office stated. “CTE may be found in the brains of decedents with a history of repeated exposure to head trauma. The science around this condition continues to evolve, and the physical and mental manifestations of CTE remain under study.”
CTE is a brain disease caused by repeated blows to the head. For years, it has been most closely associated with NFL players, but as NBC News and ESPN reported, Tamura never played football beyond high school. He began playing tackle football at age six, continuing through his teens in California, where he often played as a running back and defensive back—positions that left him vulnerable to frequent and forceful hits. After high school, Tamura moved to Nevada, where he worked in private security and later in casino surveillance.
Despite never reaching the professional level, Tamura’s case is far from unique. “We know that we have a lot of cases like this. We know high school football players can get CTE,” said Chris Nowinski, co-founder and CEO of the Concussion Legacy Foundation, in an interview with NBC News. Nowinski argued that Tamura’s diagnosis should serve as a wake-up call to coaches and sports leaders nationwide. “We don’t need any more research to convince high school coaches to change the rules of the game. There needs to be a will to do it.”
Indeed, a 2023 study led by Dr. Ann McKee, a leading neurologist in CTE research, found that 41% of brains from athletes under the age of 30 who played contact sports showed signs of CTE. The study examined 152 brains of young athletes, aged 13 to 29, who exhibited symptoms during their lives. Their brains were donated to the Understanding Neurologic Injury and Traumatic Encephalopathy (UNITE) Brain Bank. The findings underscore a growing concern: CTE is not just a risk for professional athletes but for anyone exposed to repeated head injuries, especially at a young age.
Tamura’s struggles extended beyond neurological symptoms. According to ESPN and NBC News, he suffered from chronic migraines, depression, insomnia, and had a documented history of mental health crises. Law enforcement in Las Vegas was called twice for mental health checks during his time there, including a 2022 incident in which his mother expressed concern he might harm himself. In that call, she told police he was being treated for depression, concussions, and chronic migraines. Tamura also had a mental health hold in 2024 and an arrest in 2023 at a Las Vegas casino, though prosecutors declined to file charges.
While CTE is associated with symptoms like memory loss, depression, and impaired judgment, experts caution against drawing direct lines between the disease and violent behavior. “The physical and mental manifestations of CTE remain under study,” the New York City medical examiner noted. Dr. Ross Zafonte, a brain injury specialist at the University of Missouri, told NBC News that “many factors affect behavior and researchers do not yet know the full depth of Tamura’s mental health history. We have to remember this is an evolving and changing piece of science.”
Still, Tamura’s case joins a grim list of high-profile incidents involving CTE. Former NFL player Aaron Hernandez, who died by suicide in 2017 after being convicted of murder, was found to have one of the most severe cases of CTE for his age. In 2021, ex-NFL player Phillip Adams fatally shot six people before killing himself, and was posthumously diagnosed with CTE. Most recently, the death by apparent suicide of former Pro Bowl running back Rudi Johnson reignited calls for greater research and prevention, though it is unclear if Johnson had CTE.
The NFL first publicly acknowledged the link between football and CTE in 2016. In a statement following the shooting, the league said, “We continue to grieve the senseless loss of lives, and our hearts remain with the victims’ families and our dedicated employees. There is no justification for the horrific acts that took place. As the medical examiner notes, ‘the science around this condition continues to evolve, and the physical and mental manifestations of CTE remain under study.’”
In the wake of Tamura’s shooting, calls for reform have grown louder. The National Federation of State High School Associations estimates that over 300,000 high school athletes in the U.S. suffer concussions each year. Since 2019, the association has recommended limiting full contact during practice and reducing total playtime per week in football and ice hockey. Helmet-to-helmet hits are now prohibited, and other measures have been introduced to reduce risk, though experts like Nowinski argue more must be done.
As the investigation into Tamura’s life and motives continues, one thing is clear: the intersection of sports, mental health, and brain injury is a complex and urgent issue, demanding attention from medical professionals, lawmakers, and sports organizations alike. For the victims’ families and the wider community, the tragedy at the NFL headquarters is a stark reminder of the human cost behind statistics and scientific debates.
For those struggling with mental health or in crisis, help is available through the Suicide & Crisis Lifeline at 988 or online at 988lifeline.org.
