The
actus reus — sometimes called the
external elements of a crime — is the
Latin term for the "guilty act" which, when proved
beyond a reasonable doubt in combination with the
mens rea, i.e., the "guilty mind", produces criminal
liability in
common law-based
criminal law jurisdictions Canada,
New Zealand,
England,
Scotland and the
United States. In the United States, some crimes also require proof of an
attendant circumstance.
The
mens rea is the
Latin term for "guilty mind" used in the
criminal law. 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 that "the act does not make a person guilty unless the mind is also guilty". Thus, in
jurisdictions with
due process, there must be an
actus reus accompanied by some level of
mens rea to constitute the crime with which the defendant is charged (see the technical requirement of
concurrence). The exception is
strict liability crimes (in the civil law, it is not usually necessary to prove a
subjective mental element to establish liability, say for breach of
contract or a
tort, although if intentionally committed, this may increase the measure of
damages payable to compensate the
plaintiff).
