In an interview with Writer Unboxed in 2007, Launer revealed that the studio had initially wanted to get rid of the colorful character of Vinny’s unemployed hairdresser/car expert girlfriend. Launer was forced to add a scene, specifically requested by the studio president, to the second draft in order to keep the character in the movie. He said, “He wanted Vinny’s girlfriend to complain that he’s not giving her enough attention.”
Launer said that he eventually, “figured out a way where they’d HAVE to keep her and embellished her character … she does complain, but at least apologizes for bringing it up, and you don’t hate her for bringing it up largely because it’s funny. … Now, I thought if she brought this up at this point where he is simply going through hell—he should be pissed off. And he is. So he kinda tears into her.” In the end, the scene which features Mona Lisa’s tirade about her “biological clock”, became one of his favorites in the entire script.
The Film's Director Never Even Saw 'The Karate Kid' Before Casting Ralph Macchio
Director Jonathan Lynn talked about casting the role in the DVD commentary, “I was very eager to have Ralph Macchio in the movie, I must confess, I had never actually seen ' The Karate Kid' ."
Lynn went on to say, "I watched him in a couple of videos that his agent sent and I thought he was just perfect for the part. … He’s very good in the movie.”
Vinny Was Based on Guys from Joe Pesci’s Neighborhood Growing Up
The actor, who grew up in New Jersey, later admitted that Vinny's character was based on people he knew when he was growing up.
In an interview with The Movie Show in 1992, Pesci said there were a lot of people like that in smaller neighborhoods, like the one he lived in, so he used these characters as inspiration for Vinny.
Will Smith Almost Played Stan Rothenstein
Actor Mitchell Whitfield had just completed his move from New York to Los Angeles when he heard that auditions for 'My Cousin Vinny' were happening in New York and decided to fly back for the screen test.
Whitfield told Abnormal Use that Will Smith was also up for the role! He must have made an impression, because Whitfield got the part of Stan and had to drop 25 pounds in order to play him.
Marisa Tomei Was Relatively Unknown When She Got the Part
When she was cast as Mona Lisa Vito, Marisa Tomei did not have a lot of big screen experience. Lynn talks about his decision to cast her in the DVD commentary, explaining that he'd seen a performance where Tomei played a 1920s blonde flapper, but he could tell she was incredibly funny and talented. Soon after, Tomei auditioned for 'My Cousin Vinny' and nailed it.
According to the director, he knew he made the right choice after reviewing the dailies of the first scene they shot with her, in which Mona Lisa and Vinny arrive in Alabama. The way she tells him, “Oh, yeah, you blend,” was all he needed.