Douglas Harper's Etymology Dictionary
Latin phrase meaning "guilty mind."
n. (context legal English) a guilty mind, a conscious knowing by the perpetrator that the act he/she committed was illicit
n. (law) criminal intent; the thoughts and intentions behind a wrongful act (including knowledge that the act is illegal); often at issue in murder trials [syn: malice aforethought]
Mens rea (; Latin for "guilty mind") in criminal law, is viewed as one of the necessary elements of some :crimes. The standard common law test of criminal liability is usually expressed in the Latin phrase, actus reus non facit reum nisi mens sit rea, which means "the act is not culpable unless the mind is guilty". Thus, in jurisdictions with due process, there must be an actus reus, or "guilty act", accompanied by some level of mens rea to constitute the crime with which the defendant is charged (see the technical requirement of concurrence). As a general rule, criminal liability does not attach to a person who merely acted with the absence of mental fault. The exception is strict liability crimes.
In civil law, it is usually not necessary to prove a subjective mental element to establish liability for breach of contract or tort, for example. However, if a tort is intentionally committed or a contract is intentionally breached, such intent may increase the scope of liability as well as the measure of damages payable to the plaintiff.
Therefore, mens rea refers to the mental element of the offence that accompanies the actus reus. In some jurisdictions, the terms mens rea and actus reus have been replaced by alternative terminology. In Australia, for example, the elements of the federal offenses are now designated as "fault elements" or "mental elements" (mens rea) and "physical elements" or "external elements" (actus reus). This terminology was adopted to replace the obscurity of the Latin terms with simple and accurate phrasing.
Usage examples of "mens rea".
In such cases the mens rea, or actual wickedness of the party, is wholly unnecessary, and all reference to the state of his consciousness is misleading if it means anything more than that the circumstances in connection with which the tendency of his act is judged are the circumstances known to him.