Ambulance Chaser: Vinny intended to be a personal injury lawyer. When he notices a man wearing a neck brace, he immediately starts questioning him of the circumstances, but loses interest once he realizes there's no case.
Book Dumb: Vinny took six tries to pass the bar exam and often gets tripped up by basic legal procedure, but he's very skilled at debunking evidence and putting together arguments against the prosecution.
Bunny-Ears Lawyer: Vinny is a street-smart guy with a great talent for putting together and presenting an argument. He also required six tries to pass the bar exam and somehow managed to do it without understanding basic aspects of law and trial procedure. He defends himself by saying that he barely had time to study while working in a garage.
Ditzy Genius: Vinny is very astute and good at thinking on his feet. He's also shown to be pretty knowledgeable when he applies himself to it.
Fish out of Water: It's not a stretch to say Vinny is very out of place in rural Alabama, and it takes him a while to adjust to his new surroundings. For instance, he is incapable of getting any rest in a cabin in the middle of the woods, but sleeps like a baby through a prison riot while spending the night in jail.
Hell-Bent for Leather: Wears a leather jacket to his first appearance in court, before Judge Haller makes him change it out for a suit.
Large Ham: Joe Pesci's clearly having a ball in the part, particularly in the courtroom scenes.
Pint-Sized Powerhouse: He's a fairly small guy (Joe Pesci stands 5'4"), but managed to punch out a redneck at least twice his size.
Self-Made Man: Well, he did put himself through law school by working in an automotive garage.
Sherlock Scan: Can tell a lot about a car just from a photograph of tire tracks. According to Bill, he isn't limited to automotive knowledge in this, as he was able to heckle a magician by figuring out all his tricks in real time. Also notices tiny details when interviewing the three witnesses (time it took to prepare breakfast, view out their window, thickness of their glasses), allowing him to counter their testimony.
Tacky Tuxedo: At one point he is forced to show up in court wearing a hideous old maroon tux, though it's not like he had much of a choice.
Took a Level in Badass: Goes from being inexperienced and completely out of his element into a competent lawyer.
Brainy Brunette: Dark-haired and intelligent, especially in the automotive field.
Brooklyn Rage: Like Vinny, she's from Brooklyn and is very no-nonsense and argumentative.
Bunny-Ears Lawyer: Who'd have thought an out-of-work hairdresser would be such an expert on cars?
Chekhov's Hobby: Her knowledge of cars is mentioned offhand by Vinny in their first scene and later proves crucial to winning the case.
Deadpan Snarker: Quite a few times, but notably after Vinny is sent to jail a second time and tells her a little encouragement would be nice, prompting her to retort:
Lisa: Support? Is that what you want? I'm sorry, you were wonderful in there! The way you handled that judge... ooh, you are a smooth talker! You are, you are!
I Have Brothers: She attributes her extensive knowledge of automobiles to coming from an entire family of mechanics: her father, her brother, and her uncles all worked as mechanics and she herself was in the business for a while before becoming a hairstylist.
Lady Swears-a-Lot: She has a very colorful vocabulary, to the point Vinny asks her, "What is it with you and that mouth?"
Large Ham: Particularly when advocating against shooting a harmless baby deer or complaining about her biological clock running out before Vinny can win a case.
Screw This, I'm Outta Here!: She puts up with a lot from Vinny throughout the movie, even when genuinely trying to be helpful, and decides to bolt just before the final act. Luckily Vinny catches her before she can leave and it's her testimony that plays a crucial part in saving Bill and Stan.
Slap-Slap-Kiss: Vinny and Lisa are constantly arguing, but as seen with the "leaky faucet" discussion they seem to prefer it that way. Though even she has her limits, as shown when Vinny chastises her for not being helpful.
Decoy Protagonist: He and Stan are the main characters for the first 15 minutes of the movie, which show how they got arrested for murder and armed robbery. Once Vinny and Lisa show up, they are largely relegated to the background.
Thicker Than Water: Due to them being cousins, he is reluctant to replace Vinny with another, more qualified, lawyer, even though losing the case will cost him and Stan their lives. He believes Vinny has what it takes to win the case, and is ultimately proven right.
Stan Rothenstein (Mitchell Whitfield)
Ambiguously Jewish: Ambiguous only in that it's never outright stated, but he has a Jewish last name, is from New York and derogatorily calls Vinny a "putz" at one point.
Jerkass Has a Point: Not a jerk, but his initial mistrust of Vinny is completely understandable, given that Vinny has had no prior courtroom experience and ends up getting himself sent to jail twice before finally turning the situation in the boys' favor.
Lovable Coward: He is very anxious regarding the situation he and Bill find themselves in.
Open Mouth, Insert Foot: He babbles about how corrupt, racist and backward the people of the South supposedly are while surrounded by many of the townsfolk (which almost certainly didn't win him any favors in court).