Montana Code Annotated

Mont. Code Ann. § 45-2-103 (2026)

General Requirements Of Criminal Act And Mental State

✓ current as of May 2026

Find cases: SyfertCases citing this section MT-LEGleg.mt.gov JustiaTitle on Justia CornellLII Search CasesGoogle Scholar

TITLE 45. CRIMES

CHAPTER 2. GENERAL PRINCIPLES OF LIABILITY

Part 1. Definitions and State of Mind

General Requirements Of Criminal Act And Mental State

45-2-103. General requirements of criminal act and mental state. (1) Except for deliberate homicide as defined in 45-5-102(1)(b) or an offense that involves absolute liability, a person is not guilty of an offense unless, with respect to each element described by the statute defining the offense, a person acts while having one of the mental states of knowingly, negligently, or purposely.

(2) In deliberate homicide under 45-5-102(1)(b), the offender must act while having the mental state of purposely or knowingly only as to the underlying felony referred to in 45-5-102(1)(b).

(3) The existence of a mental state may be inferred from the acts of the accused and the facts and circumstances connected with the offense.

(4) If the statute defining an offense prescribes a particular mental state with respect to the offense as a whole without distinguishing among the elements of the offense, the prescribed mental state applies to each element.

(5) Knowledge that certain conduct constitutes an offense or knowledge of the existence, meaning, or application of the statute defining an offense is not an element of the offense unless the statute clearly defines it as an element.

(6) A person's reasonable belief that the person's conduct does not constitute an offense is a defense if:

(a) the offense is defined by an administrative regulation or order that is not known to the person and has not been published or otherwise made reasonably available to the person and if the person could not have acquired the knowledge by the exercise of due diligence pursuant to facts known to the person;

(b) the person acts in reliance upon a statute that later is determined to be invalid;

(c) the person acts in reliance upon an order or opinion of the Montana supreme court or a United States appellate court later overruled or reversed; or

(d) the person acts in reliance upon an official interpretation of the statute, regulation, or order defining the offense made by a public officer or agency legally authorized to interpret the statute.

(7) If a person's reasonable belief is a defense under subsection (6), nevertheless the person may be convicted of an included offense of which the person would be guilty if the law were as the person believed it to be.

(8) A defense based upon this section is an affirmative defense.

History: En. 94-2-103 by Sec. 1, Ch. 513, L. 1973; amd. Sec. 11, Ch. 359, L. 1977; R.C.M. 1947, 94-2-103; amd. Sec. 1, Ch. 580, L. 1979; amd. Sec. 5, Ch. 485, L. 1981; amd. Sec. 2, Ch. 610, L. 1987; amd. Sec. 9, Ch. 354, L. 1995.

Notes of Decisions

Cited in 67 cases (8 in the last 5 years), 1979–2026 · leading case: State v. Brown, 755 P.2d 1364 (Mont. 1988).

Sort: Relevance Newest Treatment

State v. Brown, 755 P.2d 1364 (Mont. 1988). · cites it 18× “Despite the fact that there is no internal mental state requirement in § 45-9-101(1), MCA, the offense of criminal sale of dangerous drugs is subject to the requirements of § 45-2-103(1), MCA, and the State is thus required to prove the offense was committed either purposely or…”

State v. Pierce, 647 P.2d 847 (Mont. 1982). · cites it 18× “First, section 45-2-103(1)(2), MCA, requires that the State prove defendant negligently caused the injuries and to prove that he negligently used a weapon.”

State v. C. Christensen, 2020 MT 237 (Mont. 2020). · cites it 6× “Section 45-2-103(1), MCA, provides, “Except for deliberate homicide .”

State v. Lambert, 929 P.2d 846 (Mont. 1996). · cites it 12× “While a person's state of mind can rarely be proven by direct evidence, the existence of a mental state may be inferred from the acts of the accused and the facts and circumstances connected with the offense, § 45-2-103(3), MCA, and may be demonstrated circumstantially.”

State v. Mills, 428 P.3d 834 (Mont. 2018). · cites it 13× “In addition to revising the elemental formulation of specific crimes, the 1973 Code replaced the common-law concepts of specific and general intent with various described criminal mental states (purposely, knowingly, negligently) as separately defined by § 45-2-101(35), (43),…”

State v. Jackson, 2009 MT 427 (Mont. 2009). · cites it 4× “Although Jackson attempts to minimize Janis's testimony because Janis *1221 testified he did not see the gun in Jackson's hand at the time of the first shots, there was much he did see.”

State v. Martin, 2001 MT 83 (Mont. 2001). · cites it 4× “" The jury convicted Martin of attempted deliberate homicide, and he contends the evidence was insufficient to prove he acted with the purpose of causing Heinle's death.”

State v. B. Hamernick, 2023 MT 249 (Mont. 2023). · cites it 11× “” Section 45-2-103(1), MCA. As the SIWOC statute requires the mental state of “knowingly,” the defendant must act “knowingly” with respect to each element described by the statute.”

State v. Averill, 2001 MT 161 (Mont. 2001). · cites it 9× “He argues, however, that under § 45-2-103(1), MCA, he was lacking the requisite intent to commit three of the four probation violations occurring on March 14 which the District Court *110 found him to have committed, specifically the offenses of leaving Cascade County,…”

State v. Starr, 664 P.2d 893 (Mont. 1983). · cites it 6× “It is therefore subject to section 45-2-103, MCA, providing generally for mental states.”

State Ex Rel. Booth v. Montana Twenty-First Jud. Dist., 1998 MT 344 (Mont. 1998). · cites it 6× “Section 45-2-103, MCA. ¶ 24 In this case, it cannot be said that Booth's conduct of driving his vehicle while under the influence of alcohol and negligently causing the death of two people meets the statutory definition of "same transaction.”

State v. Nichols, 734 P.2d 170 (Mont. 1987). · cites it 5× “’ Section 45-2-103, MCA.” Certain acts regarded as peculiarly dangerous create a reasonable risk of death.”

Show all 67 citing cases →

— Mont. Code Ann. § 45-2-103(1) — 11 cases

State v. Brown, 755 P.2d 1364 (Mont. 1988). “Despite the fact that there is no internal mental state requirement in § 45-9-101(1), MCA, the offense of criminal sale of dangerous drugs is subject to the requirements of § 45-2-103(1), MCA, and the State is thus required to prove the offense was committed either purposely or…”

State v. C. Christensen, 2020 MT 237 (Mont. 2020). “Section 45-2-103(1), MCA, provides, “Except for deliberate homicide .”

State v. Averill, 2001 MT 161 (Mont. 2001). “He argues, however, that under § 45-2-103(1), MCA, he was lacking the requisite intent to commit three of the four probation violations occurring on March 14 which the District Court *110 found him to have committed, specifically the offenses of leaving Cascade County,…”

State v. Mills, 428 P.3d 834 (Mont. 2018). “In addition to revising the elemental formulation of specific crimes, the 1973 Code replaced the common-law concepts of specific and general intent with various described criminal mental states (purposely, knowingly, negligently) as separately defined by § 45-2-101(35), (43),…”

State v. McDole, 734 P.2d 683 (Mont. 1987).

— Mont. Code Ann. § 45-2-103(1)(2) — 1 case

State v. Pierce, 647 P.2d 847 (Mont. 1982). “First, section 45-2-103(1)(2), MCA, requires that the State prove defendant negligently caused the injuries and to prove that he negligently used a weapon.”

— Mont. Code Ann. § 45-2-103(2) — 1 case

— Mont. Code Ann. § 45-2-103(3) — 35 cases

State v. Jackson, 2009 MT 427 (Mont. 2009). “Although Jackson attempts to minimize Janis's testimony because Janis *1221 testified he did not see the gun in Jackson's hand at the time of the first shots, there was much he did see.”

State v. C. Christensen, 2020 MT 237 (Mont. 2020). “Section 45-2-103(1), MCA, provides, “Except for deliberate homicide .”

State v. Martin, 2001 MT 83 (Mont. 2001). “" The jury convicted Martin of attempted deliberate homicide, and he contends the evidence was insufficient to prove he acted with the purpose of causing Heinle's death.”

State v. Reim, 2014 MT 108 (Mont. 2014).

State v. Kelman, 915 P.2d 854 (Mont. 1996).

— Mont. Code Ann. § 45-2-103(4) — 8 cases

State v. Lambert, 929 P.2d 846 (Mont. 1996). “While a person's state of mind can rarely be proven by direct evidence, the existence of a mental state may be inferred from the acts of the accused and the facts and circumstances connected with the offense, § 45-2-103(3), MCA, and may be demonstrated circumstantially.”

State v. Hovey, 2011 MT 3 (Mont. 2011).

State v. Lemmon, 692 P.2d 455 (Mont. 1984).

State v. Lundblade, 625 P.2d 545 (Mont. 1981).

— Mont. Code Ann. § 45-2-103(5) — 4 cases

State v. Blalock, 756 P.2d 454 (Mont. 1988).

State v. Dobson, 2001 MT 167 (Mont. 2001).

State v. McGregor, 2017 MT 156 (Mont. 2017).

— Mont. Code Ann. § 45-2-103(6) — 2 cases

Commonwealth v. Kratsas, 764 A.2d 20 (Pa. 2001).

— Mont. Code Ann. § 45-2-103(6)(c) — 2 cases

Walker v. Commonwealth, 127 S.W.3d 596 (Ky. 2004).

Harold C. Ostrosky v. State of Alaska Roger v. Endell, Comm'r of Corr., 913 F.2d 590 (9th Cir. 1990).

Annotations are extracted automatically from the opinions in the Syfert caselaw corpus and ranked by authority, recency, and treatment. Dots show Syfertize treatment of the citing case itself.