Indiana Code Title 30. Trusts and Fiduciaries § 30-4-2-12

(a) The terms of the trust may not require the trustee to commit a criminal or tortious act or an act which is contrary to public policy.

(b) A trust with terms which violate subsection (a) of this section is invalid unless the prohibited term is separable.  If the prohibited term is separable, only it is invalid and the remainder of the trust is valid.