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Mens rea

Mens rea is a criminal law concept which focuses on the mental state of the accused and requires proof of a positive state of mind such as intent, recklessness, or willful blindness. In jurisdictions with due process, some level of mens rea is always a required element of the crime with which the defendant is charged, and must be proven by the prosecution. Most civil law claims also incorporate some level of mens rea as a required element, with the exception of strict liability torts.

Mens rea comes from the Latin phrase; Actus non facit reum nisi mens sit rea, translated An act does not make a man guilty unless his mind be also guilty. Mens rea roughly translates to guilty mind.

An illustration of mens rea would be the difference between hurting someone voluntarily and accidentally; in the first case, the mens rea, the intention to hurt, is present but not in the second one.

Another example: if the intention to kill or to act in a way that can predictably lead to the death is not proved, one can not be found guilty of the crime of murder because the definition of this crime includes this condition (to be convicted, you need both the mens rea and the Actus reus, also known as the "psychological" and "material" elements); without the mens rea for murder, the accusation will usually turn into manslaughter, a different but similar crime that does not require the same mens rea.

Mens rea under the Model Penal Code

Prior to the 1960s, mens rea was a very slippery, vague and confused concept. Since then, the formulation of mens rea set forth in the Model Penal Code has been highly influential throughout North America in clarifying the discussion of the different levels of mens rea.

The four levels of mens rea set forth in the MPC are:

(1) Purposely - Express purpose to commit a specific crime against a particular person

(2) Knowingly - Knowledge that one's actions would certainly result in a crime against someone, but did not specifically intend to commit that crime against the particular victim which one is accused of injuring

(3) Recklessly - Knew that one's actions had an unjustifiable risk of leading to a certain result, but did not care about that risk ("reckless disregard"), and acted anyway

(4) Negligently - Did not intend to cause the result that happened, but failed to exercise a reasonable duty of care to prevent that result (which includes failing to become aware of the risk of that result)

Some commentators like to add on a fifth uncodified level (technically applicable only in civil lawsuits and not criminal prosecutions):

(5) Strict liability - Did everything possible to prevent the result that happened, but will be held liable anyway as a matter of public policy, because the government wants to force all such similarly situated persons to always exercise the maximum reasonable duty of care under such circumstances

Examples of mens rea in statutes

Model Penal Code: A person commits murder if he (1) purposely or knowingly (2) causes the death of a human being.

Common Law: (a) It shall be unlawful for a person to cause the death of a human being with malice aforethought. (b) A violation of this section is murder in the second degree. ..

See also

Last updated: 05-06-2005 14:26:00