According to the Director's Commentary, the tape that George Jung leaves for his father near the end of the movie is a verbatim transcript of a tape that the real George Jung recorded under similar circumstances.
A lot of Johnny Depp's dialogue was improvised, including the scene where they are trying to find a place to put all their money from selling coke and his line "We're gonna need a bigger boat" (a quote from Jaws (1975)).
The real George Jung was released from prison on June 2, 2014. He was due to be freed in November, but was released early after fulfilling a plea bargain by testifying against his co-conspirators. Jung will reside in a San Francisco halfway house until he re-adjusts to society.
When George is in the courtroom the first night before he finds out that Barbara's sick, the words that he is reciting to convince the judge that he is innocent are lines from Bob Dylan's song "It Ain't Me Babe" and Woody Guthrie's song "Pretty Boy Floyd".
When George is sharing a cell in prison with Diego, George is seen reading a paperback while reclining on his top bunk. The book is "Hell's Angels" written by Hunter S. Thompson, the author whom Depp previously portrayed in the movie Fear and Loathing in Las Vegas (1998).
In one scene, George (Johnny Depp) has his suitcase searched at an airport. When a pair of women's underwear are found, George says "Hard to break old habits." This is an obvious reference to Depp's previous film Ed Wood (1994) in which Depp's character is well known for wearing women's underwear.
The scene at the hotel (where Johnny Depp gets shot in the shoulder) was supposed to be taking place in Miami Beach. It was filmed at a small hotel outside of downtown Los Angeles, where it was raining, and about 40 degrees Fahrenheit. Shooting had to be delayed briefly, because the actor's breath could be seen on film.
While the closing scene claims Kristina never visited George in prison, there have since been unconfirmed reports that the two have reconciled. She is even billed as "Clerk," although her scene did not make the final cut.
During an interview with comedian Gilbert Gottfried at the 2017 Tribeca Film Festival, director Barry Levinson recounted that he first became involved with show business reluctantly accompanying his friend George to an acting class in 1968. As Levinson became more and more interested in the class, his friend's interest waned and the two eventually lost touch when Levinson relocated to be closer to the film and television industry. Although he was aware that George was selling marijuana at the time, Levinson had no idea what became of his friend until he saw this film and learned that he became the largest cocaine dealer in America. The two reconnected following Jung's 2015 release from prison, when Jung recounted watching Levinson at the Oscars during his incarceration.
George Jung hid marijuana in an RV, and delivered it to customers. Emma Roberts, who played George's daughter, later starred in We're the Millers (2013), a comedy about a fake family who smuggles marijuana in an RV.