ACTUS REUS & MENS REA
"Actus non facit reum nisi mens sit rea", or "an act does not make a man guilty unless his mind be also guilty (Burgess, 2004, p.8)." In criminal law, for an individual to commit a crime, there must be present two elements. They are: Actus Reus (meaning guilty act or omission); and
Mens Rea (meaning guilty mind).
Actus Reus is the guilty act or omission in the commissioning of a crime. In short, it is what the offender does or doesn't do which results in a crime taking place. Mens Rea is the guilty mind behind the crime. It is what tells the offender that what they are doing or not doing is wrong but they do it regardless. An act can be described as an action carried out by the offender in order to commit the crime. On the other hand, an omission is the opposite, where an offender neglects to take action to prevent a crime. To omit something is to leave it out, failure to act (Halsey, 1986, p. 704). For example: Watching someone have a heart attack and no attempting to render assistance or call an ambulance could be classified as an omission. The failure to render assistance or calling an ambulance resulted in the person's death.
These elements can also be described as a physical element and a fault element. The Commonwealth Criminal Code of Australia sets out that the physical elements of an offence must include an element of conduct involving the offender. Conduct may be an act, an omission, a state of affairs or some combination of those elements (AIJA Magistrates' Conference, July 2001, p. 6). The Code also defines five distinct fault elements: intention, knowledge, recklessness, dishonesty and negligence (AIJA Magistrates' Conference, July 2001, p. 6).
Majority of crimes require not only the proof of an action or omission having been perpetrated by the offender but a guilty mind must also be established before a person can be convicted. In other words, the prosecution must prove not only that the accused committed the offence but that s/he did it knowing that it was against the law; that their act (or omission) was done with the intent to commit a crime.
However, an act or omission must be voluntary. That is the offender carried out the act or failed to act on purpose, knowing full well of the consequences. For example: Lucy ran her husband down with their old Tarago, knowing that her actions would probably result in his death or at least serious injury. For an act or omission to be voluntary, the offender must have known and thought about the results of their actions and knowing these continued with the act or omission regardless of the consequences.
The elements of a crime can be shown clearly via the following diagram:
(Burgess, 2004, p. 9)
DEFENCES TO CRIME
The elements of a crime are affected by the defences to crime. Where the Prosecution must prove beyond reasonable doubt that there was some voluntary act (actus reus) and a guilty mind (mens rea).The defence must only prove the defence upon the balance of probabilities. Defences to different crimes include: intoxication; self-defence; accident; provocation; battered woman syndrome; mental impairment; automatism; consent; and necessity. The following is a brief description of each and how mens rea is affected by them:
Intoxication: someone who is charged with an offence may be found not guilty of an offence if they were so heavily under the influence of alcohol and/or drugs that they did not possess the intention to commit the crime they are accused of. However, it has been found by the Parliament of NSW that juries in Victoria are reluctant to accept intoxication as a defence (Mullen, 2000, pp.5-6). The defence of intoxication therefore would prove that the accused had no mens rea or no guilty mind so the accused cannot be found guilty of an offence. For example: In the ACT, rugby player Noa Nadruku was acquitted of assaulting his wife and two other women...