Removing an elected official from office is not an easy undertaking. This answer is not a substitute for independent legal advice. If your question pertains to the removal of a trustee as the chairman of the board, Montana law provides that the trustee, once elected, shall serve until the next organizational meeting when officers are elected.
"The presiding officer of the trustees of any district shall serve until the next organization meeting and shall preside at all the meetings of the trustees in accordance with the customary rules of order. The presiding officer shall perform the duties prescribed by this title and any other duties that normally pertain to a presiding officer." Mont. Code Ann. §20-3-321(2).
If your question pertains to the removal of a trustee from the board, there are several sections of Montana statutory law that apply, as follows:
Mont. Code Ann. §20-3-310, Trustee removal. "Any trustee may be removed from his trustee position by a court of competent jurisdiction under the law providing for the removal of elected civil officials. When charges are preferred against a trustee and good cause is shown, the board of county commissioners may suspend such trustee from his trustee position until the charges can be heard in the court of competent jurisdiction."
8th of February, 2010