Authorities arrested Royko in April 2005 after he went into a Chicago bank with a ski mask and a fake bomb and demanded money.
He pleaded guilty to the attempted bank robbery charge last March.
Andersen ordered Royko jailed Aug. 6 after the defendant admitted he'd smoked marijuana while on bond. He said he had done so only one time.
Andersen said it was time for Royko to get on with his sentence and prepare to start a new life once he is released.
Royko's Defense"I drove to the city. I remember bits and pieces. It's like I was a robot, or I was dreaming. I parked the car," said Robert Royko.
And he walked into a bank in his old neighborhood with a box he claimed was a bomb and demanded money from a teller who thought he was joking. An off-duty cop in the bank lobby quickly put him under arrest. There was no bomb.
"I can't believe I did that. I can't believe I'm still going to, I can't believe it," said Royko.
The only way to explain what happened, Royko contends, is the powerful stew of prescription medications he was on. He went, he says, from 150 pills a month to more than 600 - Valium, Depakote for depression, Vicodin for back pain - then the anti-psychotic Zyprexa which Royko abruptly stopped a week before the bank robbery attempt because of suicidal feelings.
"I wasn't doctor hopping. I wasn't pharmacy hopping, and it's all proof. It's all in writing," said Royko.
While some medical experts have supported Royko's claim, federal prosecutors argued that his actions on that April day were deliberate, pre-meditated, and his claim of diminished metal capacity doesn't hold up under federal law. The judge in the case agreed. So Royko could not use the "meds made me do it" as his defense though that was an argument he says he wouldn't surrender.
"How do I spend my whole life not a criminal and then all of a sudden - boom - I'm on 660 pills, then I try to rob a bank. That's not a coincidence," said Royko.
The judge in the case has expressed empathy for Royko but says most people who attempt to rob banks do suffer from mental issues.
The Associated Press contributed to this report.