On July 28, 2025, 27-year-old gunman Shane Tamura entered a New York City office building that is home to the National Football League’s headquarters. He shot and killed four people and injured one other before killing himself.
In a note found in his wallet, he claimed he had chronic traumatic encephalopathy, or CTE , a degenerative brain condition believed to develop from repeated traumatic brain injuries. He asked experts to study his brain .
CTE has received much attention over the past two decades as multiple NFL players have been diagnosed with the condition after their deaths. The 2015 movie “Concussion ,” about a forensic pathologist named Dr. Bennet Omalu who documented the first case of CTE in an NFL player, also highlighted the issue.
The gunman in the New York City sh