Mont. Code § 7-12-4306
When no protests have been delivered to the clerk of the city council within 15 days after the date of the first publication of the notice of the passage of the resolution of intention or when a protest shall have been found by the city council to be insufficient or shall have been overruled or when a protest against the extent of the proposed district shall have been heard and denied, immediately thereupon, the city council shall be deemed to have acquired jurisdiction to order the proposed improvements. Before ordering any of said proposed improvements, the city council shall pass a resolution creating the special improvement lighting district in accordance with the resolution of intention theretofore introduced and passed by the city council.
§ 7-12-4306, MCA