The planned Fox series, which explores life in a pre-Batman Gotham City through the eyes of a young Jim Gordon (Ben McKenzie, "Southland," "The OC") has added Donal Logue. Here's the official word, with casting catch-up:
Donal Logue (Sons of Anarchy, Vikings, Copper) has been cast as Detective Harvey Bullock in FOX and Warner Bros. Television’s one-hour drama project GOTHAM, which has a series commitment at the network.
Character description: Jim Gordon’s partner and mentor, the rough-around-the-edges Detective Harvey Bullock plays loose with police procedure, but he gets results … and he does it with old-school, forceful panache.
Based upon characters published by DC Comics, GOTHAM is a drama exploring the origin stories of Commissioner James Gordon and the villains that made Gotham famous.
Bruno Heller (The Mentalist, Rome) wrote the pilot script and will serve as executive producer. Danny Cannon (the CSI series, Nikita) will direct and executive produce the pilot.
Series regulars cast to date are Ben McKenzie as Detective James Gordon, Zabryna Guevara as Captain Essen, Erin Richards as Barbara Kean, Sean Pertwee as Alfred Pennyworth and Robin Lord Taylor as Oswald Cobblepot (aka The Penguin).