Ind. Code § 31-17-2-21 : FAMILY LAW AND JUVENILE LAW — FAMILY LAW: CUSTODY AND VISITATION RIGHTS — ACTIONS FOR CHILD CUSTODY AND MODIFICATION OF CHILD CUSTODY ORDERS —17-2-21 - Modification of child custody order TEXT PDF (a) The court may not modify a child custody order unless: (1) the modification is in the best interests of the child; and (2) there is a substantial change in one (1) or more of the factors that the court may consider under section 8 and, if applicable, section 8.5 of this chapter. (b) In making its determination, the court shall consider the factors listed under section 8 of this chapter. (c) The court shall not hear evidence on a matter occurring before the last custody proceeding between the parties unless the matter relates to a change in the factors relating to the best interests of the child as described by section 8 and, if applicable, section 8.5 of this chapter. IC 31-17-2-21 Pre-1997 Recodification Citation: 31-1-11.5-22(d), (e), (f). As added by P.L. 1-1997, SEC.9. Amended by P.L. 96-1999, SEC.9.