Tenn. Code Ann. § 6-20-208

Whenever, in the opinion of the mayor, city manager or any two (2) commissioners the welfare of the city demands it, the mayor or the recorder shall call special meetings of the board of commissioners upon at least twelve (12) hours written notice to each commissioner, the city manager, recorder, and city attorney, served personally or left at such person's usual place of residence. Each call for a special meeting shall set forth the character of the business to be discussed at such meeting and no other business shall be considered at such meeting.