Mens rea
Mens rea is Latin for
"guilty mind". In criminal law, it 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 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. 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.