Mont. Code Ann. § 72-3-610

A personal representative is a fiduciary who shall observe the standards of care applicable to trustees under the laws of the state of Montana. A personal representative is under a duty to settle and distribute the estate of the decedent in accordance with the terms of any probated and effective will and this code and as expeditiously and efficiently as is consistent with the best interests of the estate. The personal representative shall use the authority conferred upon the personal representative by this code, the terms of the will, if any, and any order in proceedings to which the personal representative is party for the best interests of successors to the estate.