Indiana Code Title 36. Local Government § 36-8-22-9

Sec. 9. (a) An employee organization is the exclusive recognized representative of the employees of an employer if:

(b) After December 31, 2007, an employer shall conduct an election to determine an exclusive recognized representative if at least thirty percent (30%) of the employees of the employer sign a petition requesting such an election.  The election shall be conducted at least thirty (30) but not more than sixty (60) days after the employer receives the petition.

(c) An employee organization becomes the exclusive recognized representative of the employees of the employer if it receives more than fifty percent (50%) of the votes cast in an election conducted under subsection (b).

(d) An election under subsection (b) to determine an exclusive recognized representative may not be conducted more often than once every two (2) years.