Driving through Alabama in their 1964 Buick Skylark convertible, Billy Gambini and Stan Rothenstein, college students from New York who just got scholarships to UCLA, shop at a convenience store and accidentally shoplift a can of tuna. After they leave, the store clerk is robbed and killed, and Billy and Stan are arrested for the murder. Due to circumstantial evidence and a confession to the shoplifting that is misconstrued as one to the shooting, Billy is charged with murder, and Stan as an accessory. Billy's mother reminds him there is an attorney in the family: his cousin Vinny. Vincent LaGuardia Gambini travels there, accompanied by his fiancée, Mona Lisa Vito. Although he is willing to take the case, Vinny is a personal injury lawyer from Brooklyn, newly admitted to the bar, and with no trial experience.

Vinny manages to fool the trial judge, Chamberlain Haller, about being experienced enough for the case. His ignorance of basic courtroom procedures, dress code, and his abrasive attitude cause the judge to repeatedly hold him in contempt. Much to his clients' consternation, Vinny does not cross-examine any of the witnesses in the preliminary hearing. Except for lack of a murder weapon, it appears that the district attorney, Jim Trotter III, has a strong case that will lead to convictions. After Vinny's poor showing at the hearing, Stan fires him and uses the public defender, John Gibbons, and nearly convinces Billy to do the same.

Despite his missteps, Vinny shows that he is able to make up for his inexperience with an aggressive and perceptive questioning style. Vinny quickly discredits the testimony of the first three witnesses, and Billy and Stan's faith is restored.

On the trial's third day, Trotter produces a surprise witness, FBI analyst George Wilbur, who testifies that the pattern and chemical analysis of the tire marks left at the crime scene are identical to the tires on Billy's Buick. With only the lunch recess to prepare his cross-examination and unable to come up with a strong line of questioning, Vinny lashes out at Lisa. However, Vinny realizes that one of Lisa's photos holds the key to the case: the flat and even tire marks going over the curb reveal that Billy's car could not have been used for the getaway.

After requesting a records search from the local sheriff, Vinny drags Lisa into court to testify as an expert witness. During Vinny's questioning, Lisa testifies that only a car with an independent rear suspension and positraction could have made the tire marks, which rules out Billy's 1964 Buick Skylark. However, one model of car with these features is the similar-looking 1963 Pontiac Tempest. Vinny re-calls George Wilbur, who confirms this. Vinny then re-calls the local sheriff, who testifies that two men who fit Billy and Stan's descriptions were just arrested in Georgia for driving a stolen green Pontiac Tempest, and were in possession of a gun of the same caliber used to kill the clerk. Trotter moves to dismiss all charges. The judge congratulates Vinny and, as they drive away, he and Lisa bicker about their wedding plans.

Box office

With a budget of $11 million, My Cousin Vinny was more successful than anticipated, grossing $52,929,168 domestically and $11,159,384 in the foreign markets, bringing its overall total to $64,088,552.

Critical reception

The film received generally positive reviews. On Rotten Tomatoes, the film holds a rating of 85%, based on 52 reviews. The site's consensus reads, "The deft comic interplay between Joe Pesci and Marisa Tomei helps to elevate My Cousin Vinny's predictable script, and the result is a sharp, hilarious courtroom comedy." Roger Ebert of The Chicago-Sun Times gave My Cousin Vinny a mixed 2.5 stars out of a possible 4. He declared that despite Macchio's co-star billing the actor was given little to do, and the film seemed adrift until "lighting strikes" with the final courtroom scenes when Gwynne, Pesci and Tomei all gave humorous performances.

Tomei won the Academy Award for Best Supporting Actress at the 65th Academy Awards in 1993.

Director Lynn has a law degree from Cambridge University, and lawyers have praised the accuracy of My Cousin Vinny's depiction of courtroom procedure and trial strategy, with one stating that "he movie is close to reality even in its details. Part of why the film has such staying power among lawyers is because, unlike, say, A Few Good Men, everything that happens in the movie could happen—and often does happen—at trial". One legal textbook discusses the film in detail as an "entertaining extremely helpful introduction to the art of presenting expert witnesses at trial for both beginning experts and litigators", and criminal defenders, law professors, and other lawyers use the film to demonstrate voir dire and cross examination.

Seventh Circuit Court of Appeals judge Richard Posner praised My Cousin Vinny^[10] as being

particularly rich in practice tips: how a criminal defense lawyer must stand his ground against a hostile judge, even at the cost of exasperating the judge, because the lawyer's primary audience is the jury, not the judge; how cross-examination on peripheral matters can sow serious doubts about a witness's credibility; how props can be used effectively in cross-examination (the tape measure that demolishes one of the prosecution's eyewitnesses); how to voir dire, examine, and cross-examine expert witnesses; the importance of the Brady doctrine ... how to dress for a trial; contrasting methods of conducting a jury trial; and more.

John Marshall Law School professor Alberto Bernabe wrote that "Vinny is terrible at the things we do teach in law school, but very good at the things we don't":^[11]

[How to] interview clients, to gather facts, to prepare a theory of a case, to negotiate, to know when to ask a question and when to remain quiet, to cross examine a witness forcefully (but with charm) in order to expose the weaknesses in their testimony

United States Supreme Court Justice Antonin Scalia cited My Cousin Vinny as an example of the principle that a client can choose his own lawyer,^[12] but United States Senator John Kennedy told District Court nominee Matthew S. Petersen that having seen the film did not qualify one to be a federal judge during a disastrous 2017 hearing when Peterson could not answer basic legal questions.^[13] The authors of Reel Justice: The Courtroom Goes to the Movies (2006) gave the film its highest rating along with several films based on real trials, such as Judgment at Nuremberg and Breaker Morant.^[14] In 2008 the ABA Journal ranked the film #3 on its list of the "25 Greatest Legal Movies",^[5] and in 2010 ranked Pesci's character as #12 on its list of "The 25 Greatest Fictional Lawyers (Who Are Not Atticus Finch)".^[15]

Lynn, an opponent of capital punishment, believes that the film expresses an anti-death penalty message without "preaching to people", and demonstrates the unreliability of eyewitness testimony. Lawyers find the film appealing, according to the director, because "there aren't any bad guys", with the judge, prosecutor, and Vinny all seeking justice. Lynn stated that both he and Launer sought to accurately depict the legal process in Vinny, favorably comparing it to Trial and Error, for which he could not make what he believed were necessary changes.^[6]

In an interview on March 14, 2012, the film's screenwriter, Dale Launer, talked about a sequel he had written involving Vincent Gambini practicing law in the United Kingdom. Marisa Tomei dropped out. The studio hired another screenwriter to rework the script without Tomei's character. Eventually, the project was shelved.^[16]

In 2017, author Lawrence Kelter began a My Cousin Vinny novel series with Back to Brooklyn, which is intended to be in the spirit of The Thin Man series. With the setting updated to contemporary times, the series depicts the further cases of Vinny Gambini with Mona Lisa operating as his investigator.^[17]

Pesci later reprised the Vincent LaGuardia Gambini character for his 1998 album Vincent LaGuardia Gambini Sings Just for You, which contains the song "Yo, Cousin Vinny." The album cover portrays Pesci in a red suit similar to the usher suit he wore in the film.

• Trial film
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