Jim Gordon and a couple others were the only ones on the police force who wasn't corrupt. Loeb used to be commisoner but Gordon took his place. Gordon works with Harvey Bullock and Renee Montoya other police officers. He also works with Batman at night and formerly Harvey Dent during day with the law before he turned to Two Face. He has a daughter Barbara who is secretly Batgirl until she got paralysed by Joker which traumatised him. He had a son too who became evil.