Dallas Cowboys player Marshawn Kneeland who died by suicide diagnosed with CTE brain disease

NFL player Marshawn Kneeland was suffering from stage 1 chronic traumatic encephalopathy (CTE) when he died by suicide last year, scientists have said. Researchers at Boston University's CTE Center made the diagnosis through a postmortem brain tissue analysis of the Dallas Cowboys' 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," said the centre's director, Dr Ann McKee. Stage 1 is the mildest of CTE's four stages, in which headaches and loss of attention or concentration are common symptoms. Kneeland's family said in a statement that 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 said. "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 said they tried to pull