The Defence of Self-Defence (WA) | Armstrong Legal

Call Our National Legal Hotline

1300 038 223
Open 7am - Midnight, 7 days
Or have our lawyers call you:

This article was written by April Jarmoszewicz - Solicitor - Perth

April Jarmoszewicz holds a Bachelor of Laws from Murdoch University and a Graduate Diploma of Legal Practice from the College of Law. She is admitted to practise in the Supreme Court of Western Australia and in the High Court of Australia. April has a strong passion in Criminal Law and since her admission, has worked exclusively in Criminal Law. Prior...

The Defence of Self-Defence (WA)


In a criminal trial, the accused is presumed to be innocent of the charge/s against them unless proven otherwise. An accused can raise the defence of self-defence if they believe an act was necessary in all the circumstances to defend themselves or another person from a harmful act. This article outlines how the defence of self-defence operates in Western Australia. 

Elements of Self-Defence 

The elements of self-defence are established under section 248 of the Criminal Code Act Compilation Act 1913 which states:

(2) A harmful act done by a person is lawful if the act is done in self-defence under subsection (4);

(…)

(4) A person’s harmful act is done in self-defence if – 

  1. The person believes the act is necessary to defend the person or another person from a harmful act, including a harmful act that is not imminent; and
  2. The person’s harmful act is a reasonable response by the person in the circumstances as the person believes them to be; and
  3. There are reasonable grounds for those beliefs. 

Who has the burden of proof?

In a trial, the burden is on the state to prove the charges before the court. When an accused raises self-defence, they bear an evidential burden of adducing evidence or pointing to prosecution evidence, capable of raising the issue of self-defence. This then gives rise to a reverse onus, meaning it is then up to the prosecution to prove beyond a reasonable doubt that the accused’s actions were not in self-defence. 

What is a Harmful Act?

A harmful act must be an act that forms an element of an offence under Part V of the Code. These offences comprise violent offences – for example assaults, suffocation and strangulation offences and homicides.  

Reasonable Belief 

In the decision of Zecevic v The Director of Public Prosecutions [1987] 61 ALJR 375 His Honour Mason CJ expressed that the term “reasonably believed” is to mean “not what a reasonable man would have believed, but what the accused himself might reasonably believe in all the circumstances in which he found himself”.

His Honour went on to propose that the jury should be questioned beyond a reasonable doubt whether “the accused believed that the force which he used was reasonably proportionate to the danger he believed he faced”. If the answer to this question is yes, then an accused is entitled to an acquittal. 

In the decision of The State of Western Australia v Evans [2020] WADC 40 His Honour Prior J held that the state could discharge its burden that the accused’s acts were not justified by the law of self-defence by proving beyond a reasonable doubt any one of the following four things: 

  1. That the accused did not believe that his actions were necessary to defend himself from a harmful act (subjective); or
  2. That the belief the accused held at the time that it was necessary to defend himself was not a reasonable belief and there were no reasonable grounds for his belief (objective); or
  3. That the accused’s response was not a reasonable response to the circumstances as the accused believed them to be (mixed objective/subjective); or
  4. That the belief the accused held at the time about the circumstances he faced, was not a reasonable belief and there were no reasonable grounds for his belief (objective). 

Self-Defence and Murder Charges

Sections 248(3) of the Act states:

  1. If – 
    1. A person unlawfully kills another person in circumstances which, but for this section, would constitute murder; and
    2. The person’s act that causes the other person’s death would be an act done in self-defence under subsection (4) but for the fact that the act is not a reasonable response by the person in the circumstances as the person believes them to be, 

The person is guilty of manslaughter and not murder. 

This means that self-defence is a partial defence to a murder charge and should an accused be found to have had a reasonable belief that he needed to defend himself, but his response was unreasonable, then this partial defence may reduce the charge of murder to manslaughter. 

Defence of Another

The defence of self-defence is also available to an accused who acted in the defence of another person. If an accused satisfies the evidential burden of the defence, then the burden is on the state to negative the defence by excluding at least one of the elements under section 248(4) of the Act beyond a reasonable doubt. 

When an act is not done in self-defence

Section 248(5) of the Act states as follows:

  1. A person’s harmful act is not done in self-defence if it is done to defend the person or another person from a harmful act that is lawful.
  2. For the purposes of subsection (5), a harmful act is not lawful merely because the person doing it is not criminally responsible for it.

If you require legal advice or representation in any legal matter, please contact Armstrong Legal. 

Armstrong Legal
Social Rating
4.8
Based on 349 reviews
×
Legal Hotline
Open 7am - Midnight, 7 Days
Call1300 038 223