This article was written by Fernanda Dahlstrom - Content Editor - Brisbane


The Defence of Self-Defence

Self-defence is a valid defence to most violent offences in New South Wales, including assault, manslaughter and murder. If a court accepts that an accused was acting in self-defence or in defence of another person, it will acquit them of the offence. Successfully relying on the defence of self-defence requires an accused to demonstrate that they believed that their actions were necessary and reasonable in the circumstances. The defence of self defence is set out in Part 11 Division 3 of the Crimes Act 1900.

Self-defence legislation

Section 418 of the NSW Crimes Act 1900 outlines when the defence of self-defence is available. That provision states that a person is not criminally responsible for an offence if they carried out the conduct in self-defence. A person carries out conduct in self-defence if they believe their conduct is necessary:

  • to defend themself or another person; or
  • to prevent or terminate the unlawful deprivation of their liberty or the liberty of another person; or
  • to protect property from unlawful taking, destruction, damage or interference; or
  • to prevent criminal trespass to any land or premises or to remove a person committing any such criminal trespass;

AND the conduct is a reasonable response in the circumstances as the accused perceived them.

Onus of proof when raising self-defence

If a person charged with a violent offence wants to rely on the defence of self-defence, they must raise the defence. The prosecution then has to prove beyond a reasonable doubt that the accused was not acting in self-defence. To do this the prosecution must show either:

  • That the accused did not genuinely believe that it was necessary to act as they did in their defence or in defence of another;
  • That what the accused did was not a reasonable response to the danger, as they perceived it to be.

What must the court consider?

There are two questions that must be asked by a court when an accused raises self-defence. These are:

  • If the answer to the first question is yes, is there also a reasonable possibility that the accused’s actions were a reasonable response to the circumstances as they perceived them.

The first question is determined by considering the personal characteristics of the accused and the situation as they perceived it at the time they carried out the conduct. It is, therefore, an entirely subjective test.

The second question is determined by an entirely objective assessment of the proportionality of the accused’s response to the situation as they perceived.  The accused need not have had reasonable grounds for their belief that it was necessary to act in the way they did in order to defend themselves. It is sufficient if the accused genuinely held that belief.

The jury is not assessing the response of a reasonable person but the response of the accused. In making that assessment it is obvious than some of the personal attributes of the accused will be relevant just as will be some of the surrounding physical circumstances in which the accused acted. Therefore, matters such as the age of the accused, their gender, or the state of his or her health may be regarded by the jury.

What if the accused was intoxicated?

If the accused was intoxicated at the time the acts were committed, their intoxication will be taken into account when the court is assessing their defence of self-defence. However, their intoxication will only be relevant to the assessment of the belief they held as to what conduct was necessary in their self-defence in the circumstances they perceived. A person who is drunk may perceive circumstances differently to a sober person. However, the accused’s intoxication will not be taken into account when assessing whether their response was reasonable in the circumstances.





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