The defence of self-defence is provided for under the Crimes Act 1900. A person carries out conduct in self-defence if and only if the person believes his or her act is necessary in order to defend himself or herself and that the conduct is a reasonable response in the circumstances as he or she perceives them.
Self-defence can also apply to situations of preventing or terminating unlawful deprivation of liberty, protecting property, and preventing or terminating criminal trespass.
The Crown must prove beyond reasonable doubt the act was not done by the accused in self-defence. To do this the Crown must prove one of two issues beyond reasonable doubt, either:
- The accused did not believe at the time of the act that it was necessary to do what he or she did in order to defend himself; or
- The act by the accused was not a reasonable response in the circumstances as he or she perceived them.
The onus of proof
It is for the Crown to prove beyond reasonable doubt that the person did not carry out the conduct in self-defence.