Tennessee Code Title 56. Insurance § 56-18-103

The corporate powers of a mutual life insurance corporation shall be exercised by, and its business and affairs shall be under the control and government of, a board of directors composed of not less than fifteen (15) nor more than twenty-one (21) natural persons who are policyholders and who are at least eighteen (18) years of age, and at least seven (7) of whom are residents and citizens of this state.