In April, Phillip Adams killed six people — including two children, ages 9 and 5 — then turned the gun on himself, dying at the age of 32. On Tuesday, we learned a likely reason why: Adams’ brain was severely damaged after playing football for 20 years, including for six NFL teams. He had chronic traumatic encephalopathy (CTE), a condition often found in people who have suffered head trauma.

That is, people like football players, who collide with each other at high speeds dozens of times a game.

“I don’t think [Adams] snapped,” said Dr. Ann McKee, who directs the CTE Center at Boston University. “It appeared to be a cumulative progressive impairment. He was getting increasingly paranoid, he was having increasing difficulties with his memory, and he was very likely having more and more impulsive behavior.”

This is far from the first football-related CTE horror story. In 2012, Kansas City linebacker Jovan Belcher killed his girlfriend, then shot himself in front of the team’s coach and general manager. That same year, Junior Seau — who was one of the league’s leading stars for two decades — killed himself. Five years later, former New England Patriots tight end Aaron Hernandez hanged himself in prison, where he was serving a sentence for murdering a friend. These are just a few examples: The list of CTE-impaired former players who have died violently is long and getting longer. 

There are skeptics of the CTE-football connection. To be fair, it’s a difficult phenomenon to research: The condition is diagnosed only after a person has died, when doctors can directly examine the subject’s brain. (That may change soon.) So studies that show high rates of CTE among former players tend to involve subjects whose families already suspected a problem, which arguably skews the results. And there are those who argue that football is a violent game: Is it any wonder it attracts people who might be inclined to violence outside the gridiron? 

Still, the news about Adams is one more reason to think caution is warranted. And the NFL has implemented a number of rule changes over the last two decades to protect players from concussions — though a study last year suggested those changes haven’t actually reduced the number of injuries. It seems likely there’s no way to fix the game in a way that preserves what players and fans love about it while also making it safe. 

It’s tempting to call for a ban on the game, but it’s not realistic: 23 of the top 25 most-watched telecasts this year are NFL games, and college football is like a religion in the South. The game isn’t going anywhere — Americans know the problems and keep on watching.

But you do have to wonder if it’s ethical to watch and support a game that inflicts so much damage on the men who play it and potentially causes those men to spread death and misery to others. Maybe we should find something else to do on Sunday afternoons.