The chief adviser on Senate matters says Lidia Thorpe is eligible to be a senator despite her claim she pledged allegiance to Queen Elizabeth’s ‘hairs’ when she was sworn in to parliament.

Clerk of the Senate Richard Pye, who is the main adviser to the Senate president on proceedings, said on Monday there was no ‘test of sincerity’ when asked about Senator Thorpe’s swearing-in ceremony.

‘The idea that we would think that perhaps there’s not due reverence or due regard being had to this constitutional requirement should somehow interfere with the ability of a democratically elected Senate to continue taking their part in the Senate, takes the point a bit too far,’ Mr Pye told Senate estimates.

He confirmed Senator Thorpe would have pledged allegiance by signing her oath anyway, as legal experts and other parliamentarians have pointed out.

‘In this case, the words that were spoken are the same words that appear in the test role,’ he said.

‘Senator Thorpe by signing them was attesting to the fact that those were the words that she had spoken.

‘And the President countersigned it to say that the oath, the affirmation has been properly made and subscribed before her.’

Senator Thorpe was forced to walk back her claim that she did not say her senatorial oath correctly after it sparked questions around her eligibility.

She told the ABC she only recalled swearing allegiance to the Queen’s ‘hairs’ rather than ‘heirs’.

‘If you listen close enough, it wasn’t her ‘heirs’, it was her ‘hairs’ that I was giving my allegiance to and now that they are no longer here, I don’t know where that stands,’ she said.

After the remarks prompted some to question the legality of her position, Senator Thorpe has denied the mispronunciation was deliberate.

The Senator told Sky News she ‘spoke what I read on the card,’ on which ‘heirs’ was written.

‘Now forgive me… my English grammar isn’t as good as others, and I spoke what I read, so I misspoke,’ she said.

‘So to have this country question, and particularly people like (Peter) Dutton and other senators from his party, for them to question my legitimacy in this job is an insult.

‘And they can’t get rid of me, so I’ve got another three and a half years, I’m sorry for those who don’t like me, but I’m here to do a job.’ 

The Greens-turned-independent made the claim after her expletive-ridden protest during the royal visit last month.

The King had just finished speaking in the Great Hall of Parliament House when Ms Thorpe roared out a torrent of abuse at him.

‘You committed genocide against our people, give us our land back!’ she shouted, while draped in a native fur coat.

‘Give us what you stole from us! Our bones, our skulls, our people, you destroyed our land!

‘Give us a treaty, we want a treaty in this country! This is not your land, this is not your land! You are not my King, you are not our King. You’re a genocidalist!’

As she was dragged away from the scene, she was heard yelling: ‘F*** the colony, f*** the colony.’

Ms Thorpe, who was elected as a Greens senator for Victoria before leaving that party and going independent, has often been vocal about her feelings towards the monarchy.

Last year she, along with representatives from 11 other countries, co-signed a letter urging King Charles to apologise for the effect of colonisation.