But in 1973, his role as an informant was discovered and he was relocated under the Federal Witness Protection Program to California and given the alias of William Hart. He reportedly returned to the Chicago area in the 1980s after the tension of living under witness protection led to him splitting with his first wife.
Speaking with the Tribune in 1984,
O`Neal said that while he had thrived working with law enforcement, he ultimately felt he’d been ''just a pawn in a very big game.''
Until his death, he worked for an attorney in downtown Chicago, friends told the Tribune, adding that he’d contacted some acquaintances upon his return, but mostly kept to himself. O’Neal did have a relationship with his uncle, Ben Heard, his drinking buddy and confidant. Still living under the assumed name of Hart, he was at Heard’s home having beers on Martin Luther King Jr. Day just before his death. Heard said that night his nephew kept leaving to use the bathroom.
"He'd stay in there 10 or 15 minutes. The last time he stayed 20 minutes. He came out in a rage and he tried to jump out my living room window [which is on the second floor],” Heard told the Chicago Reader. “I stopped him. I grabbed him by the ankles. I wrestled with him but he broke free and he ran out the door.”
O’Neal then bolted onto a nearby expressway, police said. His death was ruled a suicide by the Cook County Medical Examiner's Office. He was 40.
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