​Marshawn Kneeland, the defensive end who played for the Dallas Cowboys and died by suicide last November in Frisco, Texas, has been diagnosed posthumously with Stage 1 chronic traumatic encephalopathy (CTE) by researchers at Boston University. The Concussion & CTE Foundation disclosed the findings on Tuesday, eight months after Kneeland’s death at age 24. Kneeland, who was a second-round pick in the 2024 NFL Draft from Western Michigan, appeared in 18 games for the Cowboys, recording 26 tackles and five tackles for loss. He also scored his first NFL touchdown shortly before his death, recovering a blocked punt in the end zone against the Arizona Cardinals.
Kneeland’s family issued a statement emphasizing that while the CTE diagnosis does not lessen the tragedy of his death, it provides important context about some of the struggles he might have faced. They asked to remember Marshawn for the person he was, rather than defining him solely by the circumstances surrounding his death. Their message also highlights the broader aim of raising awareness about the ongoing impact of brain injuries in contact sports and other high-risk activities.
To understand Kneeland’s diagnosis, it is important to know what CTE is and how it develops. Chronic traumatic encephalopathy is a progressive neurodegenerative condition characterized by the degeneration of nerve cells that are essential for thinking, feeling, and moving. This degeneration can lead to a range of symptoms, including changes in personality, memory loss, impaired judgment, and problems with motor function. CTE is strongly associated with repeated head trauma, including concussions and sub-concussive blows, and its risk can be influenced by factors such as age and genetics. Stage 1 CTE, the earliest identifiable stage, is typically marked by short-term memory problems, mild irritability or aggression, depression, and headaches. Currently, CTE can only be diagnosed with certainty after death, through neuropathological examination of brain tissue.
As the medical community continues to study CTE and its links to athletic careers and other activities involving repeated head impacts, Kneeland’s case adds to the growing body of evidence that such injuries may have long-term consequences. The discovery of Stage 1 CTE in Kneeland’s brain aligns with the pattern seen in other former athletes who have shown early signs of the condition, though it does not establish a direct cause-and-effect relationship with his life and death. Researchers and clinicians stress that a posthumous diagnosis can illuminate potential factors in a person’s mental and behavioral health, while also highlighting the need for improved safety protocols, early detection, and supportive care for athletes at all levels.
The Cowboys organization has not issued a public statement in response to the new information, but Kneeland’s family continues to advocate for greater awareness and resources dedicated to brain health in sports. They have expressed a desire to shift the focus from the circumstances of Kneeland’s death to the person he was and the challenges he faced, hoping that sharing his story will foster understanding and compassionate response to others who struggle with brain injuries and mental health issues.
In summary, Kneeland’s posthumous Stage 1 CTE diagnosis provides a clinical piece of the broader conversation about brain health in professional football and other sports. It underscores the reality that repeated head trauma may contribute to neurodegenerative changes even at a young age and serves as a reminder of the ongoing need for research, prevention, early intervention, and comprehensive support for athletes dealing with the aftermath of contact sports.