Mont. Code § 13
An attorney seeking to be admitted to practice before the court on a particular case, who is not admitted to the Bar of Montana, and who is authorized to practice law in the highest courts of another state, must at the time of his or her first appearance in a district court in Montana, or within fourteen days, and before any further proceedings in the matter, join with an attorney who is admitted to practice in Montana and who is a resident of Montana.
In order to hold secure the just, speedy and inexpensive determination of every action, such local counsel must be furnished with all factual, evidentiary and legal information necessary to act on behalf of the party and must also be vested with full and complete authority to act on behalf of and bind the party in all matters connected with the litigation.
A failure of local counsel to take any action required by the Rules of Civil Procedure or these Rules by lack of authority shall, for the purpose of imposing sanctions, be treated as a refusal to act.
§ 13, MCA