Dallas Cowboys player who died by suicide diagnosed with brain diseaseImage source, Getty ImagesByMadeline HalpertPublished7 July 2026Updated 7 hours agoDallas Cowboys football player Marshawn Kneeland was suffering from stage 1 chronic traumatic encephalopathy (CTE) when he died by suicide last year, scientists mentioned. Researchers at Boston University’s CTE Center made the diagnosis through a postmortem brain tissue analysis of the defensive lineman, who died aged 24. “Unfortunately, I was not surprised to find CTE in the brain of Mr Kneeland, because we have found this progressive brain disease in nearly half of the athletes we’ve studied who have died before the age of 30,” mentioned the centre’s director, Dr Ann McKee.Stage 1 is the mildest of CTE’s four stages, where headaches and loss of attention or concentration are common symptoms. In a statement, Kneeland’s family mentioned the diagnosis provided “important context” about some of the struggles he was facing. “We share this information to help people understand what NFL and other high-contact sport athletes might be struggling with,” they mentioned. “We continue to remember Marshawn with compassion for the person he was, rather than defining him by the final moments of his life.”Kneeland died in November 2025, after a car chase with Texas State Troopers who mentioned they tried to pull him over for a traffic violation. Police at the time mentioned he crashed his car and then fled on foot. He was later found dead from a self-inflicted gunshot wound in the early morning hours.
Kneeland was drafted by the Cowboys in the second round in 2024 and played 18 times for the team, including four starts. He started playing tackle football when he was 7 years old and was on Western Michigan University’s team before joining the Cowboys as a defensive end.
