Tennessee Code Title 8. Public Officers and Employees § 8-5-202

(b)(1) If the general assembly is not in session when such disability or incapacity on the part of the regular state treasurer occurs, the governor shall appoint a person as state treasurer, charged with the duty of performing the regular duties of the office. Such person shall serve during the emergency or until the time the general assembly shall convene and elect a person to fill the office for the continuance of the emergency.

(2) If the general assembly is in session when the regular state treasurer becomes incapacitated or disabled and therefore cannot perform the duties of the office, then the general assembly shall elect the additional state treasurer to serve during the existence of the emergency.