$pringfield (or How I Learned to Stop Worrying and Love Legalized Gambling) - S5-E10
Continuity mistake: When Marge comes home after the bogeyman incident, Homer trips over a footrest. You can see Bart sitting there however his pyjama's are a dark green color when before they were a bright green color. (00:16:35)
Chosen answer: You're right--it's a character mistake, but an explainable one. Andy probably figured that because he was doing so much work for the Warden (accounting for dirty money, kickbacks, tax compliance, etc.), that the Warden would use his power to get Andy a new trial. Sounds like a fair trade--Andy makes sure there's no way for anyone to disover the illegality of the laundering, and the Warden gets Andy pardoned. What Andy didn't realize, however, was that the Warden didn't want to risk having Andy, after his pardon & release, reveal the details of the illegal schemes that were going on. So to make sure Andy got the message that he was going nowhere and would reveal nothing, he was give the two months in solitary confinement (as you know from the movie, of course).
Matty Blast