5 U.S.C. § 5584: Claims for overpayment of pay and allowances, and of travel, transportation and relocation expenses and allowances

the authorized official; the claim is in an amount aggregating not more than $1,500; and the waiver is made in accordance with standards which the authorized official shall prescribe; or the Director of the Administrative Office of the United States Courts when the claim is in an amount aggregating not more than $10,000 and involves an officer or employee of the Administrative Office of the United States Courts, the Federal Judicial Center, or any of the courts set forth in section 610 of title 28 . if, in his opinion, there exists, in connection with the claim, an indication of fraud, misrepresentation, fault, or lack of good faith on the part of the employee or any other person having an interest in obtaining a waiver of the claim; except in the case of employees of the Government Publishing Office, the Library of Congress, the Office of the Architect of the Capitol, or the Botanic Garden, if application for waiver is received in his office, after the expiration of three years immediately following the date on which the erroneous payment of pay was discovered or three years immediately following October 21, 1968 , whichever is later; except in the case of employees of the Government Publishing Office, the Library of Congress, the Office of the Architect of the Capitol, or the Botanic Garden, if application for waiver is received in his office after the expiration of three years immediately following the date on which the erroneous payment of allowances was discovered or three years immediately following October 2, 1972 , whichever is later; in the case of employees of the Government Publishing Office, the Library of Congress, the Office of the Architect of the Capitol, or the Botanic Garden, if application for waiver is received in his office after the expiration of 3 years immediately following the date on which the erroneous payment of pay or allowances was discovered or 3 years immediately following July 25, 1974 , whichever is later; or in the case of a claim involving an erroneous payment of travel, transportation or relocation expenses and allowances, if application for waiver is received in his office after the expiration of 3 years immediately following the date on which the erroneous payment was discovered. A person who has repaid to the United States all or part of the amount of a claim, with respect to which a waiver is granted under this section, is entitled, to the extent of the waiver, to refund, by the employing agency at the time of the erroneous payment, of the amount repaid to the United States, if he applies to that employing agency for that refund within two years following the effective date of the waiver. The employing agency shall pay that refund in accordance with this section. In the audit and settlement of the accounts of any accountable official, full credit shall be given for any amounts with respect to which collection by the United States is waived under this section. An erroneous payment, the collection of which is waived under this section, is deemed a valid payment for all purposes. This section does not affect any authority under any other statute to litigate, settle, compromise, or waive any claim of the United States. an Executive agency; the Government Publishing Office; the Library of Congress; the Office of the Architect of the Capitol; the Botanic Garden; the Administrative Office of the United States Courts, the Federal Judicial Center, and any of the courts set forth in section 610 of title 28 ; and the Congressional Budget Office. the head of an agency, with respect to an agency or employee in the legislative branch; or the Director of the Office of Management and Budget, with respect to any other agency or employee.