The real George Jung was released from prison on June 2, 2014, to reside in a San Francisco halfway house. He was due to be freed in November, but was released early after fulfilling a plea bargain by testifying against his co-conspirators.
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 Lo squalo (1975)), which itself was improvised.
Director Ted Demme died less than a year later, while playing basketball. A postmortem toxicology test showed cocaine in his system.