Section 3W(4)(b) in Tamil Nadu District Municipalities Act, 1920
(b)The offices of the chairmen of the town panchayats shall be reserved for women belonging to the Scheduled Castes and the Scheduled Tribes from among the offices reserved for the persons belonging to the Scheduled Castes and the Scheduled Tribes which shall not be less than one-third of the total number of offices reserved for the Scheduled Castes and the Scheduled Tribes.