Shane Tamura, the gunman that killed four people in the deadly Midtown Manhattan shooting, had low-stage CTE, officials said Friday.
New York’s Office of the Chief Medical Examiner revealed the results Friday.
“Following a thorough assessment and extensive analysis by our neuropathology experts, OCME has found unambiguous diagnostic evidence of Chronic Traumatic Encephalopathy, also known as CTE, in the brain tissue of the decedent. The findings correspond with the classification of low-stage CTE, according to current consensus criteria,” OCME said in a statement.
Aland Etienne, Wesley LePatner, Julia Hyman and NYPD Det. Didraul Islam were all killed in the July 28 shooting by Tamura, a 27-year-old former high school football player. Tamura shot himself in the chest after killing them.
He left handwritten notes, repeatedly referencing CTE and writing, “Study my brain please. I’m sorry.”
Though Tamura never played in the NFL, investigators believe he was targeting the NFL offices inside the office building where he killed four people.
“The League knowingly concealed the dangers to our brains to maximize profits,” Tamura wrote.
The three-page note found in Tamura’s pocket said that he wanted to have his brain donated to science so it could be researched, according to law enforcement sources.
Tamura’s final note also included the name of Chris Nowinski, a leading CTE expert. CBS News New York’s Mahsa Saeidi recently spoke with him.
What is CTE?
Chronic traumatic encephalopathy, or CTE, is a brain disease that is most common in athletes who play contact sports, such as football players, ice hockey players and boxers. It is a degenerative disease, occurring after repeated head injuries cause cells in the brain to die.
“The most likely place it shows up in everybody at the beginning is the dorsolateral prefrontal cortex, so … behind the forehead, basically with the idea that when your brain twists violently, that part of your brain is moving the most,” Nowinski said. “It is killing you cell by cell. When you lose enough neurons in certain places, you will change as a person.”
Nowinski said, however, a CTE finding would not explain the shooting.
“Whatever’s in his brain is never going to be the reason for what happened. Human behavior is far too complex for that,” he said.
Dr. Anne McKee, the director of the CTE Center at Boston University, said while CTE is most talked about in professional athletes, it has also been found in student-athletes.
Tamura played high school football in California in 2014, according to articles from the Santa Clarita Valley Signal.
“Being a high school football player is certainly a possibility for CTE,” Dr. McKee said. “We have a recent study where we found about 30% of former high school players had CTE. Now that’s a very select group of people. It doesn’t mean 30% of the general population of high school football players have CTE, but it’s a distinct possibility.”
She said that CTE can occur without someone receiving a concussion, but rather, “It’s the hits that don’t cause any symptoms, the hits that we consider minor hits that the player plays right through, asymptomatic hits, but those hits can be very substantial.”
What are the symptoms of CTE?
Irritability, inattention, and behavioral changes such as aggression or impulsivity are common first indicators of CTE, according to Dr. McKee.
The damage “usually begins in small spots in the frontal lobes,” she explained. “But over time, with aging, it starts affecting widespread regions of the brain and can cause profound memory loss and even dementia.”
Symptoms of CTE do not typically appear right after someone receives a head injury, but rather develop as time goes on, according to the Mayo Clinic. The hospital says additional symptoms of CTE can include trouble thinking and planning, mood changes, suicidal thoughts and substance misuse. Patients may also have trouble with balance and walking, and may develop shaking and trouble speaking.
“We have seen individuals with CTE that have had substantial breaks with reality,” Dr. McKee added. “There’s precedence where a former football player has a break of homicidal violence and this kind of behavior is obviously something we need to prevent.”
CTE in the NFL
CTE has become more talked about in recent years as more cases of the disease are found in former NFL players. Aaron Hernandez, a former New England Patriots player and convicted murderer, was diagnosed with stage 3 CTE after his death. Dr. McKee said at the time that he had one of the worst cases of the disease she had ever seen.
Former NFL player and CBS Sports analyst Irv Cross was diagnosed with stage 4 CTE. His widow said that at the time of his death, he was seeing things.
The BU CTE Center said that out of 376 former NFL players it has tested, 345 had CTE.
The NFL has made changes in recent years to prevent head injuries, including new rules and equipment.
“The NFL has definitely made rule changes to the play of the game that make the game safer for the players, but they haven’t done enough, and they really set the stage for all high school and even college football players,” Dr. McKee said.
In 2024, the league announced that it will allow players to wear special head protection called Guardian Caps to give more protection against head injuries. Guardian Caps are soft coverings that wrap around the NFL hard-shell helmets, reducing the impact from head injuries.
The NFL also changed kickoffs to reduce full-speed tackles. But Dr. McKee said she believes the organization should be doing more.
“They need to do much more than just the helmet design, which is never going to prevent CTE. It’s really rules of play and styles of play, eliminating the hits to the head that occur in practice as well as games, paying attention to the players, monitoring the players for the number of hits they’ve sustained and actually keep track of the players over time,” she said.
Riley Rourke
Riley Rourke is a digital producer for CBS Boston. She has worked at WBZ-TV since graduating from Emerson College in 2023.
