Mont. Code § 18-7-205
Any person or any corporation or any firm or any quasi-corporation who shall violate any provision of this part or swear falsely hereunder or charge or attempt to charge the state of Montana in excess of the prices and rates herein fixed or in any manner circumvent or attempt to circumvent this part or aid or abet any other person, firm, corporation, or quasi-corporation in offense against this part shall be guilty of a misdemeanor and shall on conviction for the first offense be fined not more than $100 or be imprisoned in the county jail for not more than 3 months or both such fine and imprisonment, in the discretion of the court, and shall on conviction for each subsequent offense be fined not more than $300 or be imprisoned in the county jail for not more than 6 months or both such fine and imprisonment in the discretion of the court.
§ 18-7-205, MCA