The cardinal maxim of the criminal law is “the doing of an act does not make a man guilty unless he has a guilty mind.” The two essential elements of any crime are actus reus (the prohibited act) and mens rea (the intention).
The term actus reus presents no problem. The definition of every crime in the Penal Code recites the prohibited act and the prosecution must prove that the accused has committed the prohibited act; the facts which hay been proved must fit the offence with which the accused is charged.
The element of mens rea presents greater problems. How does the prosecution prove that a man has a guilty mind? To prove mens rea the prosecution must show that the act or omission must have been done voluntarily and secondly, that there must have been some foresight of the consequences. There may have been intention to do the act, or recklessness on the part of the accused, so that he could foresee the consequences of his act or did not care whether those consequences were brought about or not. No act is punishable if it is done involuntarily.