Cowboys player Marshawn Kneeland posthumously diagnosed with stage 1 CTE
Dallas Cowboys defensive lineman Marshawn Kneeland, who died by suicide in 2025, was posthumously diagnosed with stage 1 chronic traumatic encephalopathy (CTE), the mildest form of the brain disease linked to repeated head impacts. The diagnosis from Boston University’s CTE Center provides context for the struggles his family described; researchers caution that CTE can only be diagnosed after death and that the relationship between CTE and suicide is complex, though risk persists for athletes despite modern safety protocols.
