The standard common law test of criminal liability is expressed in the Latin phrase actus reus non facit reum nisi mens sit rea,[2] i.e. "the act is not culpable unless the mind is guilty".
[13]: 95 [14]: 84 Under the tradition of common law, judges would often require a "bad state of mind" in addition to an action or omission (actus reus) to find a criminal guilty.
[25][26][27][28] Supreme Court Justice Stephen Breyer described the distinction between the two systems in his dissent in Delling v. Idaho:[29] Case One: The defendant, due to insanity, believes that the victim is a wolf.
[32][33] Consequently, Title 18 of the United States Code does not use the aforementioned culpability scheme but relies instead on more traditional definitions of crimes taken from common law.
[34] For example, malice aforethought is used as a requirement for committing capital murder,[35][36] and the Supreme Court has applied mental states such as "willfully.
[39] This Model Penal Code ("MPC") was completed in 1962, and received praise from legal scholars for its reformulation of criminal law.
[39] Since its publication, the formulation of mens rea set forth in the Model Penal Code has been highly influential throughout the United States in clarifying the discussion of the different modes of culpability.
[5](5)[46] The MPC also recognizes culpability not because of a mental state, but for crimes that are legislatively proscribed due to the imposition of "absolute liability.
§1111, the definition of murder includes an actus reus (the unlawful killing of a human being) and a common law mens rea: malice aforethought.
By contrast with traditional common law, the Model Penal Code specifically distinguishes purpose and knowledge to avoid confusion regarding "intent" elements.
[51] Many states still adhere to older terminology, relying on the terms "intentional" to cover both types of mens rea: "purposeful" and "knowing".
[54][55] Scholars' allegations include incoherency from conflicted philosophical commitments,[56] or the federal governments' failure to explicitly adopt the Model Penal Code resulting in departure from common law precedents.
The Supreme Court of Canada has found that the Canadian Charter of Rights and Freedoms guarantees a minimum requirement for the mental state of various crimes.
Some offences exist whereby an act can be proven but there is lack of the necessary guilt of mind, such can be seen in instances where courts are unable to establish criminal intent due to persistent mental health or cognitive impairment (see, Mental Health and Cognitive Impairment (Forensic Provisions) Act (NSW) s 30).
Often in cases where the full guilty mind can not be established, statute law in Australia will provide an alternative sentencing option, such relationship can be seen in the Crimes Act 1900, s33 and 35, where s33(3) states s 35 as an alternate sentence for a finding of Grievous Bodily Harm in the event whereby the Jury is not satified that the accused held the necessary element of specific intent required for criminal liability under s 33.
However, they preferred to import it by using different terms indicating the required evil intent or mens rea as an essence of a particular offence.
All these words indicate the blameworthy mental condition required at the time of commission of the offence, nowhere found in the IPC, its essence is reflected in almost all the provisions of the Indian Penal Code 1860.
In Islamic law, intention (niyya) is a criterion for determining whether a criminal act is punishable or pardonable, or whether the penalty for such a crime is predetermined (ḥadd) or discretionary (taʿzīr).
In the 1991 US Supreme Court opinion for Cheek v. United States,[63] Byron White wrote: The proliferation of statutes and regulations has sometimes made it difficult for the average citizen to know and comprehend the extent of the duties and obligations imposed by the tax laws.
[...] Thus, the Court almost 60 years ago interpreted the statutory term "willfully" as used in the federal criminal tax statutes as carving out an exception to the traditional rule.
In R v. Klundert, for example, the Ontario Court of Appeal found as follows: [55] Section 239(1)(d) is part of an Act which is necessarily and notoriously complex.
Thus, when a person plans what to do and what not to do, they will understand the range of likely outcomes from given behaviour on a sliding scale from "inevitable" to "probable" to "possible" to "improbable".
If there is clear subjective evidence that the accused did not have foresight, but a reasonable person would have, the hybrid test may find criminal negligence.
Moreover, if there is an irrebuttable presumption of doli incapax – that is, that the accused did not have sufficient understanding of the nature and quality of his actions – then the requisite mens rea is absent no matter what degree of probability might otherwise have been present.
If the accused admits to having a motive consistent with the elements of foresight and desire, this will add to the level of probability that the actual outcome was intended (it makes the prosecution case more credible).
[71] Deceptive statements, failure to cooperate with authorities, or evasive actions made by a defendant after the commission of a crime or other wrongdoing are seen as evidence of a guilty conscience.