Revealing mistake: The film is supposed to be in Alabama, but it was actually shot in Georgia. You can see this when Vinny and Mona are first pulling into the town and they are turning left, in the shot you can see the Georgia State Highway road signs off in the distance. (00:13:20)
Revealing mistake: Joe Pesci wears face tape to hide some of his wrinkles, as well as a toupee. In a few scenes, this one most glaringly, you can clearly see the face tape. (01:35:14)
Revealing mistake: There is a scene where Vinny bodyslams the guy from the bar who owes him money. He slams him onto the pavement, but you can see the guy bounce when he hits the concrete - during filming they used some type of mattress to break his fall.
Chosen answer: He never says that it was "his" idea. The actual quote from the movie is that on "a" hunch he looked it up. From the way it is worded in the movie, it appears he said it this way in order to appear impartial in bringing any new evidence to the court's attention, not necessarily just information that would benefit the defendant's case.
Jazetopher