Originally Posted by Excelsior.
He was clearly supposed to be a character that is an opportunistic ******* at the beginning who morphs into a selfless hero, as a statement of Batman's positive influence on *******s. Yes, he was that. But it just wasn't done well. It wasn't given enough attention. He sees Batman's flaming symbol and suddenly becomes a hero. Nolan also missed the chance to milk last minute sympathy for him by giving him a hilarious death.
He finds out Gordon could be losing his job and takes it as a chance to one-up Gordon in different scenarios such as bossing rookie cops and taking Batman down, then when realizing how Gordon was right about the masked man and his underground army acts likes a good little soldier until Bane hung those special forces guys which he then decides to hide his uniform and badge and stay hidden with his wife only to find out that Batman is back and now the GCPD has a fighting chance. I like the arc myself.