Australian senator calls the Queen a coloniser while being sworn in to parliament

Indigenous senator Lidia Thorpe was told to repeat the oath of allegiance for Australian parliamentarians on Monday after she initially described the Queen as a coloniser.

Thorpe, a Greens senator for Victoria, was chided by her parliamentary colleagues, one of whom yelled, “You’re not a senator if you don’t do it properly.”

Thorpe was absent from parliament last week when other senators were officially sworn in, so took her oath on Monday morning. Walking to the Senate floor with her right fist raised in the air, Thorpe was asked to recite the words written on a card.

“I sovereign, Lidia Thorpe, do solemnly and sincerely swear that I will be faithful and I bear true allegiance to the colonising her majesty Queen Elizabeth II,” she said.

The word “colonising” is not in the formal oath.

The Labor Senate president, Sue Lines, interjected, as other senators voiced criticism and began calling to Thorpe.

“You are required to recite the oath as printed on the card,” Lines told the Greens senator.

“Please recite the oath.”

Thorpe turned to speak to a Labor senator behind her who appeared to voice further criticism, before repeating the oath as printed.

Another senator was heard to say “none of us like it”.

Thorpe later tweeted “sovereignty never ceded” as she shared a photo of her swearing-in.

Section 42 of the Australian constitution states that “every senator and every member of the House of Representatives shall before taking his seat make and subscribe” the oath.

But Prof Anne Twomey, a constitutional expert at the University of Sydney, said it was unclear whether failing or declining to make the oath would block someone from taking their place in federal parliament.

“As this is an internal proceeding in the Parliament, I doubt whether it would be ‘justiciable’ – ie I don’t think it is something that could be enforced before a court,” she told Guardian Australia.

“It is a matter for the presiding officers of the Houses to enforce section 42.”

Twomey said Thorpe could have decided not to take up her seat, if she was not prepared to swear allegiance to the Queen.

“Failure to do so would mean that she could not sit or vote. She would be entitled to other rights and privileges … However, if she failed to attend for two consecutive months without the permission of the Senate, her place would become vacant under section 19 of the constitution,” she said.

The assistant minister for the republic, Matt Thistlethwaite, last week told Nine newspapers that swearing allegiance to the Queen was “archaic and ridiculous”.

“It does not represent the Australia we live in and it’s further evidence of why we need to begin discussing becoming a republic with our own head of state,” he said. “We are no longer British.”

However, under the Australian constitution all senators and MPs must swear an allegiance to the Queen and her heirs and successors before sitting in parliament. The provision cannot be changed without a referendum, which Thistlethwaite said would only be done as part of a broader move towards a republic in a future term of government.

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Thorpe last month described Australia as a “colonial project” and said the national flag did not represent her.

“It represents the colonisation of these lands, and it has no permission to be here, there’s been no consent, there’s been no treaty, so that flag does not represent me,” she told Channel 10’s The Project.

Thorpe said she stood for parliament “to question the illegitimate occupation of the colonial system in this country”.

“I am here for my people, and I will sacrifice swearing allegiance to the coloniser to get into the media like I am right now, to get into the parliament like I am every day,” she said.