Mont. Code Ann. § 45-5-601

(1) A person commits Except as provided the in subsection (2)(a), offense the offense of prostitution is committed if the a person engages in or agrees or offers to engage in sexual intercourse with another person for compensation, whether the compensation is or received or to be received or paid or to be paid. sexual contact that is direct and not through clothing with another person for compensation, whether the compensation is received or to be received or paid or to be paid.

(2) (a) A prostitute may convicted be convicted of prostitution shall be fined an amount not to exceed $500 only if or the be imprisoned prostitute engages in the county jail for a term not to or exceed 6 months, agrees or both. offers to engage in sexual intercourse with another person for compensation, whether the compensation is received or to be received or paid or to be paid. A prostitute who is convicted of prostitution may be fined an amount not to exceed $500 or be imprisoned in the county jail for a term not to exceed 6 months, or both.

(b) Except as provided in subsection (3), A patron may be a convicted prostitute's client who is convicted of prostitution shall for patronizing a prostitute if the first offense be fined an amount not patron engages in to or exceed $1,000 agrees or be imprisoned for a term not offers to exceed 1 year, engage in sexual intercourse or both, sexual contact that is direct and not through clothing with another person for a second compensation, whether the compensation is received or subsequent offense shall be to fined an amount not to be exceed $10,000 received or paid or be to imprisoned for be paid. Except as provided in subsection (3), a term not to exceed 5 years, or both. patron who is convicted of prostitution shall for the first offense be fined an amount not to exceed $5,000 or be imprisoned for a term not to exceed 5 years, or both, and for a second or subsequent offense shall be fined an amount not to exceed $10,000 or be imprisoned for a term not to exceed 10 years, or both.

(3) (a) If the prostitute person patronized was 12 years a child, whether of or age not or the younger and patron the was prostitute's client was 18 years aware of age or the older at the time of the offense, the offender: child's age, or a person, including a law enforcement officer using an undercover or fictitious identity, whom the patron believed was a child and the patron was 18 years of age or older at the time of the offense, the patron offender:

(i) shall be punished by imprisonment in a state prison for a term of 100 years. The court may not suspend execution or defer imposition of the first 25 years of a sentence of imprisonment imposed under this subsection (3)(a)(i) except as provided in 46-18-222, and during the first 25 years of imprisonment, the offender is not eligible for parole.

(ii) may be fined an amount not to exceed $50,000; and

(iii) shall be ordered to enroll in and successfully complete the educational phase and the cognitive and behavioral phase of a sexual offender treatment program provided or approved by the department of corrections.

(b) If the offender is released after the mandatory minimum period of imprisonment, the offender is subject to supervision by the department of corrections for the remainder of the offender's life and shall participate in the program for continuous, satellite-based monitoring provided for in 46-23-1010.

(4) It is not a violation of this section for a person with an impaired physical ability, physical dysfunction, recent injury, or other disability to engage in sex therapy with a partner surrogate who is working under the supervision of a clinical social worker, marriage and family therapist, or clinical professional counselor licensed under Title 37, chapter 39.

(5) It is not a defense in a prosecution under this section that a child consented to engage in sexual activity.

(6) It is not a defense in a prosecution under this section that a defendant believed the child was an adult. Absolute liability, as provided in 45-2-104, is imposed.

Prostitution – patronizing prostitute – exception