Actus reus

The actus reus consists of more than just an act.

The components of a criminal offence are the actus reus and the mens rea.

Actus reus refers to the physical element required for criminal liability, the 'guilty act'. This can comprise of an act, an omission or a state of affairs. The defendant has to have acted voluntarily. If he has no control over his actions he can not have committed the actus reus. Automatism can be used as a defence if the defendant is not aware of or in control of his actions.

In the case of Larsonneur 1933 the defendant was being deported from Ireland back to the UK from where she had been deported as her permission to be in the UK had expired.  She was escorted back to this country by officials who then promptly arrested her for being an 'illegal alien' on arriving back in the UK because she was there without consent.  Her argument, that she did not want to be in the UK, did not assist her. This case shows that, although she did not commit the actus reus, she was found guilty because of the principle of strict liability. 

It requires the production of consequences or results i.e. the resulting death of a human being. In some 'conduct' crimes such as dangerous driving, the actus reus is the prohibited conduct itself and there is no need to establish a consequence of the act. Other crimes, 'result' crimes such as causing death by dangerous driving, will require that the act caused a consequence.

To say that actus reus means the guilty act is probably an over simplification.  It is not enough that the defendant has committed an act. The term is wider in its application and includes all the circumstances surrounding the commission of the offence including, in particular, conduct, results or consequences or states of affairs.

In some situations it also includes omissions but these are restricted to special circumstances.  Generally the rule is that there is no liability if you fail to act except if the defendant was under a legal obligation to act at the time either by statute, public duty or out of responsibility due to the defendant's position.

In the case of murder for example there must be an unlawful killing of a human being under the Queen’s peace with malice aforethought.  If the victim does not die then there may be an alternative charge of one of the more serious assaults.

The killing must be unlawful.  The killing of enemy aliens by the armed forces in warfare, lawful executions, a policeman who kills in the execution of his or her duty and members of the medical profession, in certain situations, do not incur liability for murder. 

In respect of members of the medical profession, it should be remembered that  the practice of euthanasia in this country is illegal and can constitute murder.  

A ‘human being’ must be capable of a sustained life.  The killing of a child whilst still in the womb by either the mother herself or by another person is not murder, although the guilty party could be convicted of another offence i.e. abortion.


Husband strangles wife but simply not guilty

AQA Law for A2 Fifth Edition Paperback

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