You may have a case for a lawsuit. Most states have laws against any employer who discusses the terms of your dismissal from a job, whether they are telling the truth or not, with anyone who should not be receiving that information. If an employer tells people who have no business knowing, that you were fired, or why you were fired, it's called slander. Slander does not have to be a false story to be considered slander. If you are harmed in any way, emotionally, financially, socially, or in any other way by the information that the former boss is giving out, then that can be considered slander, and can be punished by law. If you feel that you have been slandered by your former boss, you may want to contact a lawyer, or at least contact your local bureau of wage and hour.