Indiana Code Title 36. Local Government § 36-9-4-17

Sec. 17. The appointing authorities shall make appointments to the board of directors under section 15 or 16 of this chapter so that the number of directors belonging to either of the two (2) major political parties does not exceed the number belonging to the other by more than one (1).  If the appointing authorities cannot agree on the manner in which this will be done, the municipal executive shall make the appointment that results in one (1) party having more directors than the other.