Tennessee Code Title 8. Public Officers and Employees § 8-18-109

(a) Judges of courts of general sessions, sheriffs, constables, and other officers whose general duties are confined to a single county, as well as retired supreme court justices and retired inferior court or general sessions judges, shall, unless it is otherwise provided, file such oaths and certificate in the office of the county clerk.

(b) Notwithstanding any law to the contrary, the county mayor, the county clerk, judges of courts of general sessions, judicial commissioners or magistrates as authorized by a judge of the court or the county mayor, or a judge of any court of record in the county may administer the oath of office for any elected or appointed official. The oath may be administered at any time after an appointment, in the case of appointed officials, or in the case of elected officials after the election, but before the judge or public official assumes office, so long as the results of the election establishing that the person taking the oath won the election are certified by the appropriate legal authority. Even though an official may file an oath before the scheduled start of a term of office, the official may not take office until the term officially begins.