(a) The chief justice of the supreme court may temporarily assign a justice of a court of appeals to another court of appeals regardless of whether a vacancy exists in the court of appeals to which the justice is assigned.
(b) The chief justice of the supreme court may assign a qualified former or retired justice or judge of the supreme court, of the court of criminal appeals, or of a court of appeals to a court of appeals for active service regardless of whether a vacancy exists in the court to which the justice or judge is assigned. To be eligible for assignment under this subsection, a former or retired justice or judge must:
(1) have served as an active justice or judge for at least 96 months in a district, statutory probate, statutory county, or appellate court, with at least 48 of those months in an appellate court;
(2) not have been removed from office;
(3) certify under oath to the chief justice of the supreme court, on a form prescribed by the chief justice, that:
(A) the justice or judge has never been publicly reprimanded or censured by the State Commission on Judicial Conduct; and
(B) the justice or judge:
(i) did not resign or retire from office after the State Commission on Judicial Conduct notified the justice or judge of the commencement of a full investigation into an allegation or appearance of misconduct or disability of the justice or judge as provided in § 33.022 and before the final disposition of that investigation; or
(ii) if the justice or judge did resign from office under circumstances described by Subparagraph (i), the justice or judge was not publicly reprimanded or censured as a result of the investigation;
(4) annually demonstrate that the justice or judge has completed in the past state fiscal year the educational requirements for active appellate court justices or judges; and
(5) certify to the chief justice of the supreme court a willingness not to appear and plead as an attorney in any court in this state for a period of two years.

(c) An active, former, or retired justice or judge assigned as provided by this section out of the county of the justice’s or judge’s residence is entitled to receive the same expenses and per diem as those allowed a district judge assigned as provided by Subchapter C. The state shall pay the expenses and per diem on certificates of approval by the chief justice of the supreme court or the chief justice of the court of appeals to which the justice or judge is assigned. The compensation authorized by this subsection is in addition to all other compensation authorized by law.
(d) An active justice assigned out of the county of his residence as provided by this section is entitled to receive, pro rata for the time serving on assignment, supplemental compensation from the county or counties paying supplemental compensation under Chapter 31 to an associate justice of the court of appeals to which the justice is assigned.
(e) A retired justice or judge assigned as provided by this section is entitled to receive, pro rata for the time serving on assignment, from money appropriated from the general revenue fund for that purpose, an amount equal to the compensation received from state and county sources by a justice of the court of appeals to which assigned. A former justice or judge assigned as provided by this section is entitled to receive, pro rata for the time serving on assignment, from money appropriated from the general revenue fund for that purpose, an amount equal to the compensation from the state received by a justice of the court of appeals to which assigned, and from county sources, an amount equal to the compensation received from county sources by a justice of the court of appeals to which assigned. For purposes of determining the amount to be paid to a former or retired justice or judge under this subsection, the compensation received from the state by a justice of the court of appeals to which the retired justice or judge is assigned is the amount equal to the state base salary paid to a justice of that court of appeals as set by the General Appropriations Act in accordance with § 659.012(a).
(f) For the purposes of Subsection (b)(1), a month of service is calculated as a calendar month or a portion of a calendar month in which a justice or judge was authorized by election or appointment to preside.
(g) Subsection (b)(1) does not apply to a retired justice of the supreme court.
(h) Notwithstanding any other provision of law, an active district court judge may be assigned to hear a matter pending in an appellate court.