When Dwight crawls through the prison sewage pipe, he sees a "Pure Mountain Spring Water" pipe next to it, and screams "Dammit!", this is a parody of "Shawshank Redemption", where the main character in that film gains freedom from prison by crawling through a dirty sewage and waste pipe.
The song that featured during the sequence where Marge is being stalked by Dwight Diddlehopper is "Who Can It Be Now?" by Men at Work.
When Marge and Dwight are at the amusement park, you can see the ride "Dilbert's Flying Cubicle" in the background, a reference to Scott Adams's popular comic Dilbert. The theme song of the Dilbert animated series can be heard in the background for a large portion of the scene.
The ads in the school newspaper are the same text and font used by Coffee News, a small newsletter.
In the part where Bart and Lisa are watching Itchy and Scratchy, Scratchy appears to be wearing a Star Wars rebel pilot helmet when he is piloting the jet.
Curiously, even though Naegle is included on the list, she is one of Dwight's hostages, therefore making Booberella the only woman Homer can marry. Unless, Dwight wasn't intending to kill all the hostages.
This is the third episode (second involving Marge) where a Simpson meets an aggressive prisoner who turns out to be in need of a family member. The previous two were Season 15's "The Wandering Juvie" and Season 12's "Pokey Mom" (the first to involve Marge).
When Homer enters Bart' room, he has no reflection on the mirror and stays in that spot. But in the next scene, he has a reflection even though he stays in the same spot.
Bart disappears when Marge and Homer start to talk.
When Homer starts to write his Superman novel, the notebook where he was writing appears out of nowhere.
When Marge spins herself to see the hour, the bag can be seen behind her but if you see Marge' shoulder the cord is missing.
When Dwight was talking to Marge, he was spotless even though he was covered in blue tint.
The cable of the phone should've been able to extend in the way Marge do.
The phone rings although Marge answers it.
A guard should have noticed that Dwight escapes since there are a guard for each prisoner.
Also, there should be flashlights and alarms but nothing is heard or seen.
Dwight broke the prisoner outfit, but when he was watching Marge through the Jumbo-Tron he has the prisoner outfit again.
When the cops surround the bank, the police car brake lights color changes from red to white.