Mont. Code Ann. § 69-14-603

In any unincorporated community ordinarily known as a village or town where the public necessity and convenience require a railroad crossing at the intersection of the railroad with any street or highway, whether lawfully established or otherwise, which is commonly used by the public, the board of county commissioners of the county may order the construction and maintenance of such railroad crossing. Upon such order becoming final and effective, it shall be the duty of the railroad company to construct and maintain in proper condition a good and safe crossing. The board of county commissioners may order more than one railroad crossing in such unincorporated community, as provided in this section, when the public necessity and convenience require more than one such crossing to afford reasonable facilities for public travel.