Due to budget limits and to add to the realism to the movie, the director and producers chose to use real news clips from the Cleveland area from the actual events that took place in the movie.
The plot to kill the Irishman (Danny Greene) involved an unprecedented breach of FBI security when a clerk was bribed by the mob and actually stole a list of confidential informants from a top secret room. Cleveland agents acted quickly, plugging the leak and arresting their clerk.
Not only did Detroit offer tax credits for filming, the city had more of a resemblance to 1970's era Cleveland. Stevenson said while they wanted to film in Cleveland, the city had "prettied itself up" and changed, whereas Detroit was - in his opinion - still "on its knees"
Val Kilmer joined the production after he turned down the opportunity to run for governor of his home state of New Mexico.
Tommy Reid noted that getting mobster Danny Greene's story on film took 12 years. Reid, a native of New Jersey, says he learned about Greene while a student at Ohio State University. Reid went on to buy the options to the book by Rick Porrello titled "To Kill the Irishman: The War That Crippled the Mafia," on which the film is based.