20 C.F.R. § 422.906
You may request review of our ban decision every three years. The three-year cycle to request review will begin on the date we issued notice of the ban, or if you appealed, the date of our appeal decision. You must submit your request for review of a ban decision in writing to the address identified in the original notice of the ban. Your request for review should identify your name, address, Social Security number, and office that issued the notice of the ban. Your request should clearly state why we should lift the ban and provide relevant documentation that supports removal of the restriction, including medical documentation, applicable psychiatric evaluations, work history, and any criminal record. You must prove by a preponderance of the evidence (meaning that it is more likely than not) that you no longer pose a threat to the safety of our personnel or visitors or the operational effectiveness of the agency. We will notify you of our decision in writing.
20 C.F.R. §422.906