Michael Wuertz was a police detective who worked with James Gordon in the Major Crimes Unit of the Gotham City Police Department. He worked with Gordon in faking an investigation into the identity of the Batman while actually working with the masked vigilante.
Gordon, with Harvey Dent, went after the mob's money supply, but Dent didn't trust Wuertz after previously investigating him for corruption. Wuertz was working with Sal Maroni, a mob leader, against the police force, and when Gordon went to seize the mob's funds they had already been moved as the mob knew they were coming. Later, a terrorist named the Joker was hired by Maroni to kill Batman and gained access to a fundraiser for Harvey Dent by holding Wuertz at gunpoint.
Later, the Joker tried to kill Harvey Dent, but after his life was saved and the Joker arrested Dent was put into a car with Wuertz. Wuertz handed him to Maroni's men, who put him in a room full of oil barrels and blew them up, burning half of Dent's body. After escaping Gotham General Hospital, Dent then found Wuertz at a bar and confronted him about his corruption. Wuertz protested his innocence, but Dent flipped his coin which sealed Wuertz's fate, and Dent shot him.