To file a lawsuit you just need a civil attorney, but have you tried disputing the false information on your file? If you file a dispute of the bad debt, the credit reporting agency will request supporting documentation from the credit card company. If they can't provide it, the negative information will be removed. It's likely an honest mistake you're dealing with here, in which case no judge is going to give you a big punitive damages award. You might also look into the possibility that your identity has been stolen and that the bad debt is actually real but was charged by someone else using your social.