Isso é coberto pelo artigo da Wikipédia de Frank Abagnale :
While he was posing as Pan Am First Officer "Robert Black", Abagnale forged a Harvard University law transcript, passed the Louisiana Bar exam, and got a job at the Louisiana State Attorney General's office at the age of nineteen. He told a stewardess he had briefly dated that he was also a Harvard Law School student, and she introduced him to a lawyer friend. Abagnale was told the Bar needed more lawyers and was offered a chance to apply. After making a fake transcript from Harvard, he prepared himself for the compulsory exam. Despite failing twice, he claims to have passed the bar exam legitimately on the third try after eight weeks of study, because "Louisiana at the time allowed you to take the Bar over and over as many times as you needed. It was really a matter of eliminating what you got wrong."
In his biography, he described the premise of his legal job as a "gopher boy" who simply fetched coffee and books for his boss. However, a real Harvard graduate also worked for that attorney general, and he hounded Abagnale with questions about his tenure at Harvard. Naturally, Abagnale could not answer questions about a university he had never attended. Eight months later he resigned after learning the man was making inquiries into his background.
Acima da Lei é um site para advogados e deu uma olhada na alegação do filme também (com algumas boas referências):
For many lawyers, this was an anticlimactic end to a running joke in the movie. With all due respect to people who can’t pass the Louisiana bar, passing the Louisiana bar is not particularly hard (despite the test’s unusual length and civil-law components). I don’t know if you can do it in two weeks. But in a month? In six weeks? Even without going to law school, I’m not sure there is a bar exam in the country that is so hard that a reasonably intelligent person couldn’t pass it with intense study over a few months. Again, they’re not really teaching you what you need to do as a lawyer in law school, they’re just messing with how you think.
It turns out that the real life Frank Abagnale Jr. passed the LA Bar on his third try. But there wasn’t any deception involved, he eventually just passed the test. Once he earned the credentials, Abagnale says that pretending to be a lawyer was one of the easiest things to fake.