Late July is usually a time of great optimism and excitement for the NFL. Training camps are underway, preseason games are set to offer chances for rookies to shine and the highly anticipated regular season is a little more than a month away.
Monday’s shooting at the New York City building that houses the league’s offices has shaken that anticipation, as the country’s most popular sport has been affected by a uniquely American problem – gun violence. At the same time, the league has had one of its most sensitive matters – the issue of brain trauma from the game’s repeated violent hits – put under a microscope just before preseason games begin with Thursday’s Hall of Fame game in Canton, Ohio, between the Detroit Lions and Los Angeles Chargers.
When Shane Devon Tamura, a 27-year-old from Las Vegas, walked into a towering office building on Park Avenue and killed four people and himself in midtown Manhattan on Monday, it shocked New York City – it was the deadliest shooting in the Big Apple since 2000 – and rattled one of the world’s biggest sporting leagues.
In a memo obtained by CNN on Wednesday, NFL Commissioner Roger Goodell said the league employee seriously injured in the incident is “surrounded by family and members of the NFL community,” Goodell wrote. A virtual town hall was scheduled for Wednesday.
“This has been a challenging time for our entire team. Please continue to take care of yourselves and one another,” Goodell wrote in the memo.
“In the midst of this difficult time, we hold on to hope and optimism for healing and brighter days ahead.”
The profile emerging of Tamura is one that is all too familiar when it comes to mass shooters. CNN’s John Miller reported Tuesday that he was put on psychiatric holds in 2022 and 2024 – part of what police called a “documented mental health history.” The rifle he used in the incident was assembled using a part purchased by someone who police described as an “associate,” keeping him out of any background checks required by Nevada law. And, as so often happens, childhood friends said they were shocked that Tamura would have done something like this, calling him a “nice guy” who was never “problematic” while he was a student.
The words Tamura left behind in his apparent suicide note also managed to hit at one of the NFL’s most delicate issues. Papers found on Tamura’s body indicate he had grievances with the league and its handling of chronic traumatic encephalopathy, or CTE, according to a law enforcement official briefed on the investigation.
CTE is a degenerative brain disease that can be caused by repeated head trauma. It’s been associated with memory loss, confusion, impulse control problems, aggression, depression, impaired judgment and suicidal behavior. Researchers have been examining whether contact sports can increase athletes’ risk for the disease. The NFL first publicly acknowledged a connection between CTE and football in 2016.
At this point, there’s no proof that Tamura had CTE. The only way to confirm whether an individual has the disease is to examine the brain after death – something that Tamura apparently called for, according to New York City Police Commissioner Jessica Tisch.
Tisch told reporters that part of the note read: “Study my brain, I’m sorry.” Tamura, a former high school football player, shot himself in the chest – something done by other football players who have died by suicide and wanted their brains to be studied after their deaths.
A former teammate told CNN that Tamura suffered multiple concussions while playing at Golden Valley High School in the Los Angeles area. It’s not clear if Tamura was ever formally diagnosed with brain injuries and it doesn’t appear that he continued his football career after high school. A NYPD official told CNN that authorities determined Tamura had no previous connection to the NFL.
A spokesperson for the New York City Medical Examiner’s Office said Tuesday that Tamura’s brain will be examined for CTE. Even still, the words in his apparent suicide note – as reported by CNN, other media outlets and Adams – bring up a subject that the NFL would hardly have wanted to be top of mind before kickoff of Thursday’s game.
It took until 2016 for the league to say football and CTE were linked after years of avoiding taking that step. That was a year after a federal judge approved a class-action lawsuit settlement between the NFL and thousands of former players that has resulted in more than $1.5 billion in claims being paid out.
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<div class=”byline__authors byline__authors–hide-all-images”>By <div class=”byline__author”><a class=”byline__image-link vossi-byline__link” href=https://www.cnn.com/profiles/sanjay-gupta-profile><span><img height=”50″ width=”50″ class=”byline__image” src=”https://media.cnn.com/api/v1/images/stellar/prod/140326162449-sanjay-gupta.jpg?q=x_2,y_0,h_898,w_1596,c_crop/h_270,w_480/c_thumb,g_face,w_50,h_50″ alt=”” onerror=”imageLoadError(this)”/></span></a><a class=”byline__link vossi-byline__link” href=https://www.cnn.com/profiles/sanjay-gupta-profile><span class=”byline__name”>Dr. Sanjay Gupta</span></a></div>, <div class=”byline__author”><span class=”byline__name”>Amanda Sealy</span></div>, Lacey Russell and <div class=”byline__author”><a class=”byline__image-link vossi-byline__link” href=https://www.cnn.com/profiles/zach-wasser><span><img height=”50″ width=”50″ class=”byline__image” src=”https://media.cnn.com/api/v1/images/stellar/prod/170804175159-zach-wasser.jpg?c=16×9&q=h_270,w_480,c_fill/c_thumb,g_face,w_50,h_50″ alt=”CNN Digital Expansion 2016
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<div class=”timestamp__published”>PUBLISHED Jul 30, 2025, 3:11 PM ET</div>
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The NFL has taken multiple steps to try and address head injuries in the game. The league is working on developing safer protective equipment, including helmets, that reduce concussions and saw a record-low number of concussions reported in the 2024-25 season, even as it saw an increase in players self-reporting concussion symptoms. Guardian Caps – a soft-shell padding that fit over traditional football helmets – are more commonly seen in practice but can be used in games.
The league instituted a more robust concussion protocol and players who are suspected of having a brain injury are examined by an independent third-party doctor on the sidelines. In order to return to play, a player must clear the protocol but even that has its flaws, as seen by the repeated head injuries to Miami Dolphins quarterback Tua Tagovailoa.
Earlier this year, the NFL announced there was a 17% reduction in concussions in the 2024-25 season, including all practices and games in the preseason and regular season. Among the changes last year was the new kickoff rule that saw drastic changes to how players set up on kickoffs in an effort to slow down a play that resulted in high-speed collisions that led to concussions. The league said the effort worked; concussions on kickoffs were down 43% from the 2021-2023 seasons.
The league is also funding research into better understanding CTE as there is widespread agreement that there is more to learn about brain injuries.
Bob Costas, a longtime figure in sports media who has been critical of the NFL’s treatment of head injuries in the past, said on Tuesday that the league has indeed answered calls for action in the last several years.
“The NFL in the last decade has responded as best they possibly can unless you’re going to stop playing football,” Costas said in an interview with Chris Cuomo on News Nation. “You can only make it less dangerous. You can’t make it completely safe.”
For now, the league mourns. It’s unclear how the NFL will mark the shooting at Thursday’s nationally televised game between the Lions and Chargers or this weekend’s induction ceremony at the Pro Football Hall of Fame, but the incident weighed on the league’s players and coaches even as they got ready for the season on Tuesday.
CNN has reached out to the league for comment.
“The people at the league office that had to go through all that,” Kansas City Chiefs head coach Andy Reid said. “It’s a bad deal. We’ve got to try to keep peace somewhere here. There’s too much of this.”
CNN’s Lauren Mascarenhas, Casey Tolan, Allison Gordon, Curt Devine, Jeff Winter, Jessie Yeung, Jill Martin, Tina Burnside, Dianne Gallagher, Wesley Bruer, Jason Hanna and David Close contributed to this report.