Confronted by authorities in the motel parking lot, the bald, portly Unbehaun dropped his cane, raised his hands and startled police by his apparent joy at getting nabbed.
At his initial court appearance, he also bewildered his appointed lawyer.
"His first words were, 'I just want to go home," that same attorney, Richard McLeese, told the court Thursday.
For a minutes, McLeese recalled, he thought Unbehaun was saying he hoped to get bond. Then, it dawned on him what Unbehaun meant.
"It is, without a doubt, one of the saddest and most disturbing cases I've dealt with," he said.
Lead prosecutor Sharon Fairley conceded the judge faced a dilemma: Sending Unbehaun to prison could be seen as more reward than punishment to him, but setting him free would risk him committing another serious crime.
Unbehaun's unusual case also raised broader societal questions, she said in one filing.
"Did the system fail Mr. Unbehaun? Or was his inability to stay out of jail the result of his own free will?" she asked. "We may never know. But what we do know, clearly, is Mr. Unbehaun lacks the desire to lead a law-abiding life outside of prison walls."
The Chicago-born Unbehaun first went to prison at 23 for transporting a stolen car. His record includes more than half a dozen convictions, including — ironically — escaping from prison.
Media accounts from 1970 describe how he kidnapped a 19-year-old girl and left her bound to an Ohio motel bed as fled in her car. For that, he was sentenced to 25 years. His most recent decade-long prison term, for bank robbery, ended in 2011.
Unbehaun pleaded guilty in September to the 2013 bank robbery in the Chicago suburb of Niles. Prosecutors had asked for a sentence of about seven years; the defense asked for three.