A former justice or judge who is engaged in the practice of law at the time of designation as a senior justice or judge shall conclude all legal practice as soon as practicable on a timetable approved by the chief justice. The chief justice may, if warranted, withhold the issuance of the senior justice's or judge's commission pending resolution of all or any part of the former justice's or judge's practice.
T.C.A. § 17-2-307