As more research and information come to light regarding the degenerative neurological damage that occurs with repeated blows to the head, the idea that Simpson could actually be suffering from chronic traumatic encephalopathy, or CTE – the debilitating brain disease caused by brain trauma that has been linked to football players – has gained traction.
Among those who believe Simpson suffered from CTE is Dr. Bennet Omalu, the world-renowned forensic pathologist who first identified the disease in football players.
"I would bet my medical license that he has CTE," Omalu, who inspired the movie Concussion, starring Will Smith, tells PEOPLE exclusively.
Those suffering from the disease, which can only conclusively be confirmed after death by testing cross sections of brain tissue, exhibit a wide range of symptoms. These include mood swings, unjustified violent tendencies, domestic violence, criminality and exaggerated emotional reactions to every day stresses.
"Given his profile," adds Omalu, "I think it's not an irresponsible conclusion to suspect he has CTE."
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Simpson Cited 'Numerous Blows to My Head' in 2012 Court DocsSimpson, who won the Heisman Trophy in college and became the first NFL player to rush for more than 2,000 yards in a season, endured thousands impacts to the head during his playing career. But there's another factor that could plausibly make his brain even more susceptible to the disorder: He possessed what is rumored to be one of the biggest heads in the NFL, one so large he required custom-made helmets.
"If you have a bigger head that means your head is heavier," explains Omalu. "That means the momentum of your impact would be bigger. It's basic physics."
In 2012, Simpson tried to convince a Clark County Nevada judge that he suffered from some sort of concussion-related brain damage. At that time, he and his lawyers were attempting to get a new trial following his 2008 conviction for armed robbery in Las Vegas – 13 years to the day after being acquitted of the murders of Nicole Brown Simpson and Ronald Goldman.
During the initial stages of the proceedings, he and his attorney reportedly filed a sworn statement in court outlining his history of brain injuries. In the document, Simpson stated that he sustained "numerous blows to my head and/or landed on my head violently" while playing in the NFL and at USC.
Simpson added, "I was knocked out of games for such head blows repeatedly in the 1970s and other times I continued playing despite hard blows to my head during football games."
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Former Business Manager: 'There's Something Wrong With His Head and There Has Been For a Long Time'Simpson's attorney eventually abandoned this legal strategy, but the idea that he could be suffering from CTE is something that at least some of the people still in Simpson's life take seriously.
"Everybody who knows him knows there's a problem there," says his former business manager Norman Pardo, who has visited Simpson at the Nevada prison where he's incarcerated. "There's something wrong with his head and there has been for a long time."
Simpson was sentenced to 33 years in prison, but will be up for parole in 2017. Whether he actually suffers from CTE or not would not have mattered in that Nevada courtroom in 2012, says former federal prosecutor Stanley L. Friedman, a Los Angeles-based attorney.
"It might affect his punishment, but not his culpability," explains Friedman. "If someone has diminished capacity, he can still be responsible for the crime. It's more an argument in mitigation in terms of a sentence."
If Simpson in fact suffers from CTE, he may finally be facing the one sentence that no lawyer in the world can help him beat.
"That's something I've wondered about for years," says the widow of a former top NFL player who not only knew Simpson – but watched CTE slowly ravage her husband. "You just cannot tell me that O.J. isn't afflicted by this."