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Treason is an ancient offence usually associated with war. It involves a person betraying their country, especially by attempting to kill or overthrow the sovereign or government. Prosecutions for treason are rare but terrorist acts in the 21st century have returned the offence to the spotlight and led to amendments to the Commonwealth Criminal Code. The maximum penalty for all types of treason in Australia is imprisonment for life.

Commonwealth legislation

Section 80 of the Code states a person commits treason if they:

  • harm, imprison, detain, restrain or cause the death of the Sovereign, the heir apparent of the Sovereign, the consort of the Sovereign, the Governor-General or the Prime Minister;
  • start a war or prepare to start a war against the Commonwealth;
  • incite a non-citizen to make an armed invasion of the Commonwealth or a Territory of the Commonwealth.

Treason is also committed by a person who:

  • helps another person who has committed treason to escape punishment or apprehension;
  • does not inform police within reasonable time of the planning of a treason offence, or take reasonable steps to prevent that offence.

Assisting an enemy

Under the Code, a person also commits treason if they help an enemy to engage in armed conflict. Section 80.1AA states the offence involves a person who is an Australian citizen or resident engaging in conduct that will materially assist the enemy in armed conflict against the Commonwealth or Australian Defence Force. This does not apply to conduct that is solely to provide humanitarian aid.

“Materially assist” is intended to include providing money or goods, and assistance that is more than trivial.

The offence of assisting the enemy by treason was introduced in 2002 in a bid to address the issue of Australians fighting with terrorist forces. The Australian Federal Police stated:

“ … the new offence takes into consideration the increasing changes in global and political circumstances in relation to terrorism. The enhanced treason offence is required to ensure that Australians in armed conflict with a terrorist organisation, such as Al-Qa’ida, can be dealt with under Australian law, where life imprisonment is the penalty. The extended jurisdiction of the offence means that an Australian committing treason as a member of a terrorist organisation against the Commonwealth of Australia, whether within or outside of Australia can be captured under the legislation”.

State legislation

The offence of treason has been legislated by some states.

In Victoria, treason can be found at section 9A of the Crimes Act 1958, worded in a similar way to the Commonwealth Code.

In Tasmania, treason can be found at section 56 of the Criminal Code Act 1924. The language reflects the heritage of the statute. Treason is defined as being committed by any person who, for instance:

  • “kills the King, or does him any bodily harm tending to his death, or maim or wounding, or imprisonment or restraint”;
  • “levies war against the King –
    • with intent to depose him from the style, honour and royal name of the Imperial Crown of the United Kingdom of Great Britain and Ireland, or of any other of His Majesty’s dominions;
    • in order by force or constraint to compel the King to change his measures or counsels, or in order to put any force or constraint upon, or in order to intimidate or overawe, any House of Parliament or any of His Majesty’s dominions”;
  • “violates, whether with her consent or not, a Queen consort, or the wife of the eldest son if the heir apparent for the time being of the King”.

The Act also defines a person as being guilty of treason when that person:

  • is an accessory after the fact to treason;
  • conceals treason;
  • forms a plan to depose the King, levy war against the King, or “instigate any foreigner to make an armed invasion of any of His Majesty’s dominions”.

It also contains a treason crime of “inciting mutiny”, committed when a person attempts to “seduce any person serving in His Majesty’s forces by sea or land from his duty and allegiance to His Majesty”, or incite anyone to commit or plan a “traitorous or mutinous act”.

In South Australia, treason can be found in section 7 of the Criminal Law Consolidation Act 1935. It provides that anyone who “compasses, imagines, invents, devises or intends” to:

  • “deprive or depose His Majesty” of power;
  • levy war against her Majesty;
  • by force or constraint, to compel her Majesty to “change her measures or counsels”;
  • force or constrain, or intimidate or overawe, federal or state parliament;
  • “move or stir any foreigner or stranger with force” to invade any of Her Majesty’s dominions or countries;

and that person “expresses, utters or declares” this by publishing or speaking or any overt act or deed, will be guilty of treason.

For advice or representation in any legal matter, please contact Armstrong Legal.

Sally Crosswell

This article was written by Sally Crosswell

Sally Crosswell has a Bachelor of Laws (Hons), a Bachelor of Communication and a Master of International and Community Development. She also completed a Graduate Diploma of Legal Practice at the College of Law. A former journalist, Sally has a keen interest in human rights law.

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