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Extended Common Purpose


Under the criminal law, the doctrine of common purpose holds that a person can be held responsible for a criminal offence that was committed by more than one person even when they did not carry out the physical elements of the offence. This occurs on the basis that the person explicitly or tacitly agreed to the criminal conduct and did not withdraw their agreement. Under the doctrine of extended common purpose, a person can be held responsible for an offence that is committed in accordance with an agreement even when that offence goes beyond the scope of the original agreement. This is the case provided that the person foresaw the possibility of the offence being committed and did not withdraw their agreement to participate. This page outlines the doctrine of extended common purpose.

McAuliffe v The Queen

The 1995 High Court of Australia decision of McAuliffe v The Queen established the principle of extended common purpose. In that case, three young people, two of whom were brothers, went to a park near Bondi Beach in order to attack and beat up a stranger. The reasons for the attack were not explained in the judgment but the assault can be inferred as being a gay bashing. One of the offenders had a hammer and another had a stick. Two of them were skilled in martial arts. The men proceeded to attack a man who was standing near the top of a cliff and kicked him and hit him with the stick.

After the first two youths kicked and hit the man, the third youth kicked him in the chest. The man fell over the edge of the cliff into some shallow water on the rocks and died. The youths ran away from the scene and the next day, the man’s body was found in the sea below the cliff. One of the youths confessed to murder. The two brothers were found guilty of murder after a trial.

The New South Wales Supreme Court instructed the jury about common purpose.

In order to establish the existence of common purpose in this case, the prosecution needed to prove three things:

  1. all three youths had agreed to hurt someone;
  2. the one who caused the man’s death did so intending to cause serious harm; and
  3. all three youths had either planned to cause serious harm or knew that it was possible during their criminal act.

On this basis, the court found the two brothers guilty of murder.

The High Court reviewed the Supreme Court’s decision and found that the judge had correctly instructed the jury about common purpose. The High Court’s decision also introduced a new idea, that of extended common purpose.

The High Court found that a person who has formed a common purpose to commit an offence together with others can also be guilty of a crime that wasn’t part of the original plan. The court found that all that is required for this to occur is that it is proven that the person foresaw the possibility that one of the other participants might commit that other crime during the course of their criminal act and continued to participate.

Implications of extended common purpose

The doctrine of extended common purpose has been controversial. In the UK, the principle has been found to be erroneous and has been abolished. However, in Australia it remains good law. A common situation where the principle applies is where a person agrees to act as a lookout in the commission of an armed robbery, with the agreement that no harm will come to anyone. Under the principle of extended common purpose, if someone is injured or killed during the robbery, the lookout may still be held accountable for the assault or murder on the basis they knew that a weapon was present.

Responses to extended common purpose

Australian judges have been divided in their opinions on the issue of extended common purpose. The principle has been defended as being in the interests of general deterrence and n the basis that public policy requires people to be held responsible for causing harm.

Former High Court judge Michael Kirby stated that the principle represents ‘a serious unprincipled departure from the basic rule’ that intention is required for criminal responsibility. The New South Wales Law Reform Commission has recommended that the test be changed to ‘a foreseeable probability’ rather than ‘possibility’.

If you require legal advice or representation in any legal matter, please contact Go To Court Lawyers.

Fernanda Dahlstrom

This article was written by Fernanda Dahlstrom

Fernanda Dahlstrom has a Bachelor of Laws, a Bachelor of Arts and a Graduate Diploma in Legal Practice. She has also completed a Master’s in Writing and Literature. Fernanda practised law for eight years, working in criminal defence, child protection and domestic violence law in the Northern Territory and in family law in Queensland.

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