Government Code §74.056

(a) A presiding judge from time to time shall assign the judges of the administrative region to hold special or regular terms of court in any county of the administrative region to try cases and dispose of accumulated business. (b) The presiding judge of one administrative region may request the presiding judge of another administrative region to furnish judges to aid in the disposition of litigation pending in a county in the administrative region of the presiding judge who makes the request. (c) The presiding judge of an administrative region may appoint a judge in the region to serve as acting presiding judge in the absence of the presiding judge. An acting presiding judge has all the rights, duties, and powers of the presiding judge. (d) In addition to an assignment under Sections 74.003 , 75.002 , and 75.003 , the chief justice of the supreme court may assign a retiree or a former judge whose last judicial office before retirement was justice or judge of the supreme court, the court of criminal appeals, or a court of appeals to the administrative judicial region in which the retiree or former judge resides for reassignment by the presiding judge of that region to a district or statutory county court in the region. The reassignment by a presiding judge is subject to the requirements of Section 74.055 . The assignment of a retiree or former judge by the chief justice to the administrative region continues only during the period for which the retiree or former judge has certified a willingness to serve under Section 74.0551 .