Late Dallas Cowboys defensive end Marshaw Kneeland was diagnosed with chronic traumatic encephalopathy (CTE) after he died by suicide, aged 24, in November 2025, which was revealed through the test results, performed by the Concussion & CTE Foundation, released by his family.
Dr. Ann McKee, the Boston University CTE Center director and chief of neuropathology for the VA Boston Healthcare System, noted that the discovery aligned with research that covered athletes within a similar age range.
