Dixon, Illinois (CNN)  -- William Heirens, the "Lipstick Killer," is believed to be the longest-serving inmate in the United States. He turns 81 on November 15.



Diabetes has ravaged his body, but his mind is sharp.



"Bill's never allowed himself to be institutionalized," said Dolores Kennedy, his long-time friend and advocate. "He's kept himself focused on the positives."



The days are spent mostly watching television and reading magazines. Using a wheelchair and sharing a cell with a roommate in the health unit of Dixon Correctional Center, he still yearns for a chance at freedom. It is something he has not tasted since 1946.



Heirens has been locked behind bars and walls for 63 years, making inmate C06103 the longest-serving prisoner in Illinois history, state officials say.



According to Steven Drizin, the legal director of the Center on Wrongful Convictions at Northwestern University, Heirens "has served longer than anyone in the U.S. that I can find."



He was put away a year after the end of World War II. It is a dubious record, but fitting for the man dubbed the Lipstick Killer, whose crime spree remains among the most infamous in the history of Chicago, the city of Capone and Leopold and Loeb.



The scar-faced gangster and the thrill-kill pair are long gone. Heirens, however, has not slipped into the past. He lives in the present and hopes for a future outside prison. Supporters have championed his cause, convinced that he is innocent, or arguing that he has been rehabilitated, a model inmate who has served his sentence.



"Pray for my release," he wrote in a letter dated October 11.



"There is no reason to keep this man behind bars," said Drizin. "He meets all the criteria for parole."



While Drizin, who has represented Heirens since 2001, and others passionately plead for his release and prepare to re-petition the state parole board that has consistently refused to free Heirens, others are convinced he is a manipulative murderer.



"He was the bogeyman," said Betty Finn of the man convicted of strangling her sister. "I don't think you need to feel sorry for him. He chose his life and he chose his actions."



Josephine Ross was the first victim. The 43-year-old was found stabbed to death in her apartment. She was killed on June 5, 1945.



In December, police discovered the body of Frances Brown in her bathroom. She was stabbed through the neck and shot in the head. The killer left a message on the wall. It said, "for heavens sake catch me before I kill more I cannot control myself." It was scrawled in red lipstick. The press seized on the detail. The headlines would soon scream of the Lipstick Killer.



Four weeks later, an intruder used a ladder to enter the second-floor window of Suzanne Degnan's bedroom. The killer approached the sleeping 6-year-old girl and abducted her. "I was old enough to know everything that happened and remember the looks on my parents' faces," Finn said of the crime against her younger sister.



"Can you imagine as a child to have this happen? Can you imagine going to bed at night and all of a sudden your sister is not in her bed?"



There would be a ransom note demanding $20,000. But there would also be the horrific discovery of Suzanne's severed head in a sewer. Other body parts were found within days.



Chicago was gripped in fear. Scores of people were questioned, but the investigation dragged on for months without a break. One, however, came in June, when two police officers confronted a burglar near the Degnan home.



The young thief was a 17-year-old student at the University of Chicago. His name was William Heirens, and police soon became convinced he was the killer.



Drizin said Heirens was subjected to days of brutal interrogation. He also was beaten and given sodium pentothal
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