When Perry is talking to Bill Johnson in his trophy room, Johnson is holding a game football with the game score painted on it in white letters. When Johnson puts the football up on a mantle, the ball rolls and comes to a stop with the writing on the ball not showing. But when the scene moves back to Perry's perspective, the writing is visible again.
During Perry's first attempt to cross-examine Thelma Brent, Burger successfully objects to Perry's line of questioning. But the judge failed to strike Perry's question and Thelma's answer from the trial record; this turns out to be significant, when Thelma's answer conflicts with some of her later testimony.