Latin for “guilty mind.”
Criminal intent or recklessness.
The term mens rea refers to the state of mind that the prosecution must prove that a defendant had when committing a crime in order to secure conviction for that crime.
Model Penal Code – § 2.02 General Requirements of Culpability.
(1) Minimum Requirements of Culpability. Except as provided in Section 2.05, a person is not guilty of an offense unless he acted purposely, knowingly, recklessly or negligently, as the law may require, with respect to each material element of the offense.
(2) Kinds of Culpability Defined.
A person acts purposely with respect to a material element of an offense when:
(i) if the element involves the nature of his conduct or a result thereof, it is his conscious object to engage in conduct of that nature or to cause such a result; and
(ii) if the element involves the attendant circumstances, he is aware of the existence of such circumstances or he believes or hopes that they exist.
A person acts knowingly with respect to a material element of an offense when:
(i) if the element involves the nature of his conduct or the attendant circumstances, he is aware that his conduct is of that nature or that such circumstances exist; and
(ii) if the element involves a result of his conduct, he is aware that it is practically certain that his conduct will cause such a result.
A person acts recklessly with respect to a material element of an offense when he consciously disregards a substantial and unjustifiable risk that the material element exists or will result from his conduct. The risk must be of such a nature and degree that, considering the nature and purpose of the actor’s conduct and the circumstances known to him, its disregard involves a gross deviation from the standard of conduct that a law-abiding person would observe in the actor’s situation.
A person acts negligently with respect to a material element of an offense when he should be aware of a substantial and unjustifiable risk that the material element exists or will result from his conduct. The risk must be of such a nature and degree that the actor’s failure to perceive it, considering the nature and purpose of his conduct and the circumstances known to him, involves a gross deviation from the standard of care that a reasonable person would observe in the actor’s situation.
(3) Culpability Required Unless Otherwise Provided. When the culpability sufficient to establish a material element of an offense is not prescribed by law, such element is established if a person acts purposely, knowingly or recklessly with respect thereto.
(4) Prescribed Culpability Requirement Applies to All Material Elements. When the law defining an offense prescribes the kind of culpability that is sufficient for the commission of an offense, without distinguishing among the material elements thereof, such provision shall apply to all the material elements of the offense, unless a contrary purpose plainly appears.
(5) Substitutes for Negligence, Recklessness and Knowledge. When the law provides that negligence suffices to establish an element of an offense, such element also is established if a person acts purposely, knowingly or recklessly. When recklessness suffices to establish an element, such element also is established if a person acts purposely or knowingly. When acting knowingly suffices to establish an element, such element also is established if a person acts purposely.
(6) Requirement of Purpose Satisfied if Purpose Is Conditional. When a particular purpose is an element of an offense, the element is established although such purpose is conditional, unless the condition negatives the harm or evil sought to be prevented by the law defining the offense.
(7) Requirement of Knowledge Satisfied by Knowledge of High Probability. When knowledge of the existence of a particular fact is an element of an offense, such knowledge is established if a person is aware of a high probability of its existence, unless he actually believes that it does not exist.
(8) Requirement of Wilfulness Satisfied by Acting Knowingly. A requirement that an offense be committed wilfully is satisfied if a person acts knowingly with respect to the material elements of the offense, unless a purpose to impose further requirements appears.
(9) Culpability as to Illegality of Conduct. Neither knowledge nor recklessness or negligence as to whether conduct constitutes an offense or as to the existence, meaning or application of the law determining the elements of an offense is an element of such offense, unless the definition of the offense or the Code so provides.
(10) Culpability as Determinant of Grade of Offense. When the grade or degree of an offense depends on whether the offense is committed purposely, knowingly, recklessly or negligently, its grade or degree shall be the lowest for which the determinative kind of culpability is established with respect to any material element of the offense.
Staples v. United States, 511 U.S. 600, 605-606 (1994).
“As we have observed, ‘[t]he existence of a mens rea is the rule of, rather than the exception to, the principles of Anglo-American criminal jurisprudence.’ Id., at 436 (internal quotation marks omitted). See also Morissette v. United States, 342 U. S. 246, 250 (1952) (‘The contention that an injury can amount to a crime only when inflicted by intention is no provincial or transient notion. It is as universal and persistent in mature systems of law as belief in freedom of the human will and a consequent ability and duty of the normal individual to choose between good and evil’).
“There can be no doubt that this established concept has influenced our interpretation of criminal statutes. Indeed, we have noted that the common-law rule requiring mens rea has been ‘followed in regard to statutory crimes even where the statutory definition did not in terms include it.’ Balint, supra, at 251-252. Relying on the strength of the traditional rule, we have stated that offenses that require no mens rea generally are disfavored, Liparota, supra, at 426, and have suggested that some indication of congressional intent, express or implied, is required to dispense with mens rea as an element of a crime. Cf. United States Gypsum, supra, at 438; Morissette, supra, at 263.”
“(n) criminal intent; the thoughts and intentions behind a wrongful act (including knowledge that the act is illegal); often at issue in murder trials.”