Illinois state Rep. Carol Sente (D) introduces the Dave Duerson Act to Prevent CTE at a news conference Thursday in Chicago. The legislation is named for the Chicago Bears defensive back who was diagnosed with chronic traumatic encephalopathy after he killed himself at the age of 50. It would ban organized tackle football for Illinois children younger than 12. (Charles Rex Arbogast/AP)

An Illinois state lawmaker proposed a bill Thursday that would ban tackle football for children under 12. The move came a day after the reintroduction of a similar bill in New York. While both face long odds to become law, they offer another signpost in football's ongoing struggle with the damage the sport does to the brain and the threat it poses to young players.

The proposed Illinois bill was named after Dave Duerson, a former Chicago Bears defensive back who committed suicide at age 50 in 2011, shooting himself in the chest so researchers could study his brain. The New York version was named after John Mackey, a Hall of Fame tight end for the Baltimore Colts who battled severe dementia and memory loss stemming from brain injuries before his death in 2011 at 69.

"Playing with [kids] 5 years old up to 12, it's just not right," said Mackey's widow, Sylvia Mackey. "I cringe now when I see a ballplayer being tackled. His head hits the ground, his neck snaps, it bounces back up — when in the past, that wasn't even an issue."

Mackey spoke Thursday afternoon in Washington after attending a Sports & Society panel discussion at the Aspen Institute. The panel included football coaches, former players and medical professionals discussing the possibility of flag football taking over as the dominant version of the sport among young players.

In Illinois, state Rep. Carol Sente (D) introduced the bill to "help youth enjoy the game while reducing long-term health risks," according to a news release. At the Aspen Institute discussion, Robert Cantu, a leading concussion and brain trauma researcher at Boston University, said he believes children younger than 12 should not play tackle football.

Cantu said research shows brains reach their maximal developmental state between ages 10 and 12. If kids experience brain injuries at that point, he said, it can have stark effects later in life. He also said playing contact sports at a young age increases the number of subconcussive blows, which research has shown can lead to chronic traumatic encephalopathy even without a concussion.

"If you injure a brain at that early age, you have later life potential consequences," Cantu sad. "I want very much for football to be played in a safer form. I think that safer form is flag."

Scott Hallenbeck, executive director of USA Football, said the organization has not taken a position on outlawing tackle football before a specified age but said it needs to "look into" the possibility.

An NFL spokesman did not address an age restriction but did note that USA Football has taken measures, such as limits on full contact, the requirement that players who suffer a suspected head injury receive medical clearance from a concussion specialist before returning to the field and the Return to Play law (on the books in all 50 states), which can help reduce the rates of recurrent concussions.

"We hope that all youth sports will continue to take measures to reduce head contact through similar rules changes, education and improved protective equipment," the league spokesman in a statement.

While the NFL could hold significant influence if it weighed in on an age limit, many believe a change would have to come from lawmakers.

"The NFL has had a quarter-century to deal with this problem and is still suiting up 5-year-olds in body armor," said former 49ers linebacker Chris Borland, who retired at age 24 over concerns about brain injuries. "I think it'll have to come from a higher power."

At the end of Thursday's panel, Crystal Dixon came out of the audience to address the room. Dixon's son, Donnovan Hill, broke his neck playing football at 13, suffered paralysis and died of complications at 18.

"I don't hate football," Dixon said. "I don't like youth football. I would love to see a world where there's just flag football, but it's not going to happen.

"Football on every level is dangerous. We're in America. It's not going away, no matter how much we fight. No matter how much we tell our stories, it's not going away."