Senior status is a form of semi-retirement for United States federal judges. To qualify, a judge in the federal court system must be at least 65 years old, and the sum of the judge's age and years of service as a federal judge must be at least 80 years. As long as senior judges carry at least a 25 percent caseload or meet other criteria for activity, they remain entitled to maintain a staffed office and chambers, including a secretary and their normal complement of law clerks, and they continue to receive annual cost-of-living increases. Senior judges vacate their seats on the bench, and the president may appoint new full-time judges to fill those seats. Some U.S. states have similar systems for senior judges. State courts with a similar system include Iowa (for judges on the Iowa Court of Appeals), Pennsylvania, and Virginia (for justices of the Virginia Supreme Court). Statutory requirements Senior status at the federal level is defined by statute: . To qualify for senior status, §371(e)(1) requires that a judge be annually certified by the chief judge as having met at least one of three criteria: Having carried, in the preceding calendar year, a caseload involving courtroom participation which is equal to or greater than the amount of similar work which an average judge in active service would perform in three months. §371(e)(1)(a) Having performed, in the preceding calendar year, substantial judicial duties not involving courtroom participation, but including settlement efforts, motion decisions, writing opinions in cases that have not been orally argued, and administrative duties for the court to which the justice or judge is assigned. §371(e)(1)(b) Having performed substantial administrative duties, either directly relating to the operation of the courts, for a Federal or State governmental entity. §371(e)(1)(d) In addition, §371(e)(1)(e) provides that a judge not meeting any of these criteria may be certified as being in senior status by the chief judge if the criteria were not met "because of a temporary or permanent disability". Nomenclature The United States Code does not refer to senior status in its body text, although the title of 28 U.S.C. § 371 is "Retirement on salary; retirement in senior status." The term senior judge is explicitly defined by to mean an inferior court judge who is in senior status. A justice of the Supreme Court who (after meeting the age and length of service requirements prescribed in 28