(a) Any sum paid contrary to any provision of this chapter or of any rule, regulation, or order hereunder may be recovered, in an action maintained by any citizen, from any officer who made, approved, or authorized such payment or who signed or countersigned a voucher, payroll, check, or warrant for such payment, or from the sureties on the official bond of any such officer. All moneys recovered in any such action shall be paid into the Government treasury. Any citizen may maintain an action to restrain a disbursing officer from making any payment in contravention of any provision of this chapter, or of any rule, regulation or order hereunder.
(b) Any person appointed or employed in contravention of any provision of this chapter or any rule, regulation, or order hereunder who performs service, for which he is not paid, may maintain an action against the officer, or officers who purported so to appoint or employ him to recover the agreed pay for such services, or the reasonable value thereof if no pay was agreed upon. No officer shall be reimbursed by the Government at any time for any sum paid to such person on account of such services.
(c) If the Director of Personnel wrongfully withholds certification of the payroll voucher or account of any employee, such employee may maintain a proceeding to compel the Director of Personnel to certify such payroll voucher or account.