History
Tommy Carma became a detective after he saved a young woman from a street gang, though his harsh methods usually led to the perps he collared to get off on police brutality charges. At one point, he did go by the book and managed to catch a mob hitman in the act, though he was the only eyewitness. The mob tried to murder him in a car explosion, but it was his wife and daughter who were killed instead. Becoming disillusioned, he left the force and took up a Night Watchman job as a cover for his real plans.
Stealing a Batman costume from a costume company (and 6 others from other companies, either out of obsession or to cover his tracks), he took to the streets and started to murder thugs that got out on a technicality, with the media and cops thinking it was the real Batman killing these men. Eventually, the real Batman tracks Tommy to his next target and the two start to fight, with Tommy believing that he is the real article and that he is facing an imposter. The arrival of Jason Todd, the current Robin and the Robin mantle being the inspiration behind his daughter’s name, distracts Tommy enough to allow the Dark Knight to subdue him and send him to Arkham Asylum to be evaluated before his trial, clearing his own name in the process.
However, Tommy escapes by killing his two guards while at the prison gym, believing them to be the Joker and Two-Face. While on the run from the cops, he hides in a small cave and, upon further exploration, finds that it connects to the Batcave itself, where he steals a Batsuit and the Batmobile to go after Lou Spindle, the man who put the hit on Tommy in the first place. Spindle dies in the ensuing chaos and the real Batman soon arrives, not hesitant in putting Tommy down this time. He is then sent to get some help for his problems, Bruce Wayne being his benefactor.
Powers
Though an ordinary human, Tommy Carma is a formidable close range combatant, as he is proficient in boxing, karate, and is also a former marine. He also made his own ad hoc crime lab to track his targets, which belies some intellect despite his insanity.