RCW 11.100.130: Person to whom power or authority to direct or control acts of fiduciary or investments of a trust is conferred deemed a fiduciary—Liability.

Whenever power or authority to direct or control the acts of a fiduciary or the investments of a trust is conferred directly or indirectly upon any person other than the designated trustee of the trust, such person shall be deemed to be a fiduciary and shall be liable to the beneficiaries of the trust and to the designated trustee to the same extent as if he or she were a designated trustee in relation to the exercise or nonexercise of such power or authority.