Lou the Policeman is white in this episode, instead of black.
When Homer buys ice cream at the Kwik-E-Mart the containers are brown and white in the freezer. Yet when he carries a container of ice cream up the counter for purchase, the container is pink.
At the start, when Krusty puts Sideshow Bob into the canon, he puts him in feet first, with his head at the opening of the cannon, but when he falls out, his feet are at the top of the cannon, meaning he would have been put in head first.
Chief Wiggum's hair is black in this episode, along with a few other early episodes. It is not until after the first few years that Wiggum's hair becomes blue.
When Bart is holding that pull-string Krusty The Clown doll, its mouth is open in a few scenes and closed in others.
Convenience store security cameras don't have microphones because they are only used to visually identify a suspect.
Even though it's revealed that Krusty was framed, when Homer steps on "Krusty"'s foot during the hold up at the Kwik-E-Mart, the voice heard is neither Krusty's, nor Bob's.
Why was Homer the one picking Krusty out of the line up and being a witness in court? That really should have been Apu. Not only did Apu get a better look, he was the one who worked in the store it happened at.
Homer's description of Krusty to the police sketch artist isn't even right, even saying he has red hair, yet the artist comes up with a completely accurate image of Krusty.
While reading Alexandre Dumas' "The Man In The Iron Mask" to the kids, Sideshow Bob says next time would be Chapter 35, entitled "The Death of a Titan." Chapter 35 of that book is entitled "The Last Supper," where "The Death of a Titan" is the title of Chapter 50. Further, this implies he'd been reading Chapter 34, but the lines he spoke actually come from Chapter 49.