Lefty Ruggiero, portrayed by Al Pacino in the film “Donnie Brasco,” is a character based on the real-life mobster Dominick “Sonny Black” Napolitano’s associate, Benjamin “Lefty” Ruggiero. In the movie, Lefty is betrayed by Donnie Brasco, who is actually an undercover FBI agent named Joseph Pistone. Lefty is ultimately killed by the mob after the FBI operation is revealed, as they believe he allowed an informant to infiltrate their ranks.
In reality, after the undercover operation was exposed, Lefty Ruggiero was arrested and charged with various crimes. He was facing a lengthy prison sentence but died of cancer in 1994 before serving significant time. The real Lefty was not killed by the mob, but he did live the rest of his life in disgrace, having been duped by an undercover agent and blamed for letting an informant penetrate the Mafia.