Tenn. Code § 23-3-102
Judges and chancellors are prohibited from practicing law in any of the courts of this state. A newly elected or appointed judge or chancellor can practice law only in an effort to wind up the judge or chancellor's practice, ceasing to practice as soon as reasonably possible and in no event longer than one hundred eighty (180) days after assuming office. The clerks of the several courts and their deputies are also prohibited from practicing in their own courts, or in any causes commenced, brought to or carried from their courts, or commenced in any court from which an appeal lies to their court. Sheriffs and other executive officers shall not practice law in the county for which they were elected, or in any cause, originating or pending in the courts of that county. With the exception of judges, chancellors and justices, nothing in this section or any other law shall be construed to prohibit employees of the executive and judicial branches of the government of this state who are licensed to practice law in this state from voluntarily providing pro bono legal services through an organized program of pro bono legal services that receives funding pursuant to § 16-3-808 and that provides professional liability insurance for losses sustained by clients of lawyers participating in the program.
T.C.A. § 23-3-102