Ind. Code § 35-34-2-13

Sec. 13. The judge of any court having criminal jurisdiction may, upon due cause shown by petition of the prosecuting attorney of the judicial circuit, extend the terms of the members of a grand jury then convened for an additional term of three (3) months or more, as requested by the prosecuting attorney. The terms of the members of any grand jury may be so extended for successive periods of increments of three (3) months or more, to a total length of no more than two (2) years.