No word on if this is true but it seems unlikely? IMDB Pro have this:
It’s all rumoured at the moment and Joaquin is rumoured to be playing Guzman:
The police drama Prism, based on the book Color of the Prism, reflects a blending of fact and fiction into a journey of intrigue, love, betrayal, greed and tragedy in this most exciting of police stories set on the Arizona-Mexico border. Detective Antonio Castenada, backed by a crack team of federal and state law enforcement officials and the latest surveillance technology, attempts to bring down Reynaldo Guzman, a prominent businessman and drug kingpin. In masterminding the assassination of a treacherous business associate and his entire family, Guzman alienates his long-time mistress, Sara, who agrees to bring Castenada undercover into Guzman’s legitimate produce and seafood import business. The suspense is increased as Antonio is torn between his love for Margo, a crime analyst; his compassionate feeling for Sara; his loathing of Mary Elizabeth, Guzman’s accountant, whose lust for him will stop at nothing.
James Franco is also rumoured…. as well as Michael Shannon. It says a release date for December 2013 so it seems unlikely! The director is also rumoured as Tony Tarantino. He’s 73 and is known more for being an actor (no relation to Quentin).