Colorado § 18-1-504 - Effect of ignorance or mistake upon culpability.
Full text of Colorado Colorado Revised Statutes § 18-1-504 — Effect of ignorance or mistake upon culpability., with citation guidance and answers to common questions.
§ 18-1-504. Effect of ignorance or mistake upon culpability.
(1) A person is not relieved of criminal liability for conduct because he engaged in that conduct under a mistaken belief of fact, unless:
(a) It negatives the existence of a particular mental state essential to commission of the offense; or
(b) The statute defining the offense or a statute relating thereto expressly provides that a factual mistake or the mental state resulting therefrom constitutes a defense or exemption; or
(c) The factual mistake or the mental state resulting therefrom is of a kind that supports a defense of justification as defined in sections 18-1-701 to 18-1-707.
(2) A person is not relieved of criminal liability for conduct because he engages in that conduct under a mistaken belief that it does not, as a matter of law, constitute an offense, unless the conduct is permitted by one or more of the following:
(a) A statute or ordinance binding in this state;
(b) An administrative regulation, order, or grant of permission by a body or official authorized and empowered to make such order or grant the permission under the laws of the state of Colorado;
(c) An official written interpretation of the statute or law relating to the offense, made or issued by a public servant, agency, or body legally charged or empowered with the responsibility of administering, enforcing, or interpreting a statute, ordinance, regulation, order, or law. If such interpretation is by judicial decision, it must be binding in the state of Colorado.
(3) Any defense authorized by this section is an affirmative defense.
Source: L. 71: R&RE, p. 404, § 1. C.R.S. 1963: § 40-1-604.
Cross references: For other provisions concerning affirmative defenses generally, see §§ 18-1-407, 18-1-710, and 18-1-805; for affirmative defenses to particular crimes, see specific criminal provisions in articles 2 through 18 of this title 18.
ANNOTATION
Law reviews. For article, "Criminal Prosecutions under the Colorado Securities Act", see 47 U. Colo. L. Rev. 233 (1976).
Section 18-2-101 and this section may be harmonized. People v. Darr, 37 Colo. App. 143, 551 P.2d 735 (1975), aff'd, 193 Colo. 445, 568 P.2d 32 (1977).
Subsection (1)(a) of this section and § 18-2-101(1) do not conflict. Darr v. People, 193 Colo. 445, 568 P.2d 32 (1977).
No defense of impossibility in attempt prosecution. The general assembly intended that the defense of factual or legal impossibility not be available in an attempt prosecution. People v. Darr, 37 Colo. App. 143, 551 P.2d 735 (1975), aff'd, 193 Colo. 445, 568 P.2d 32 (1977).
Defendant may raise defense of general mistake of fact. A defendant may not rely on the defense of legal impossibility in a prosecution for attempted theft, but may raise the defense of general mistake of fact by alleging that he never believed the goods were stolen. People v. Darr, 37 Colo. App. 143, 551 P.2d 735 (1975), aff'd, 193 Colo. 445, 568 P.2d 32 (1977).
If the defendant does every act within his power to commit an offense and would have committed the offense if the facts had been as he believed them to be, then he may not escape criminal liability. People v. Borrego, 738 P.2d 59 (Colo. App. 1987).
A mistaken belief that one's conduct is legal does not relieve a person of criminal liability for engaging in proscribed conduct. Becker & Tenenbaum v. Eagle Restaurant, 946 P.2d 600 (Colo. App. 1997); People v. Bruno, 2014 COA 158, 342 P.3d 587; People v. Gutierrez-Vite, 2014 COA 159, 411 P.3d 119.
Mistake of law defense not available when acting upon unauthorized directions from sheriff. Sheriff is not empowered or authorized to place listening device without court order. Deputy sheriff, then, cannot rely upon such direction as a defense to his actions. People v. Lesslie, 24 P.3d 22 (Colo. App. 2000).
Reliance upon court opinion is not basis for mistake of law defense when opinion is clearly factually distinguishable. People v. Lesslie, 24 P.3d 22 (Colo. App. 2000).
Language for a mistake-of-fact jury instruction that is almost identical to the statutory language is proper. People v. Manyik, 2016 COA 42, 383 P.3d 77.
Applied in People v. Andrews, 632 P.2d 1012 (Colo. 1981); People v. Castro, 657 P.2d 932 (Colo. 1983).
Source: official Colorado text · Last verified 2026-08-27
Frequently Asked Questions About Colorado § 18-1-504
What does Colorado Revised Statutes § 18-1-504 cover?
Section 18-1-504 ("Effect of ignorance or mistake upon culpability.") is part of the Colorado Revised Statutes, the codified statutory law of Colorado. It sets out the legal rule or procedure described in the text above. Statutes are amended regularly, so always verify against the official source.
How do I cite Colorado § 18-1-504?
A common citation format is "Colorado Revised Statutes § 18-1-504" (Colorado). Legal writing may require the code abbreviation, section number, and year or edition. Match the style required by your court, professor, or publisher.
Is this the official text of Colorado law?
No. This page is for research and education and may not include the most recent amendments. For official current law, check the Colorado official source linked on this page or consult a licensed Colorado attorney.
How does Colorado § 18-1-504 apply to my situation?
Statutes are interpreted in context, and application depends on your specific facts. Only a licensed attorney in Colorado can advise on how this section applies to you. Contact your state or local bar association for a referral.
Sources & Verification
Not legal advice. Verify against the official source and consult a licensed attorney in Colorado.