Okla. Stat. tit. 60, § 1212

The terms of a trust may relieve a cotrustee from duty and liability with respect to another cotrustee's exercise or nonexercise of a power of the other cotrustee to the same extent that in a directed trust a directed trustee is relieved from duty and liability with respect to a trust director's power of direction under Sections 10 through 12 of this act.