MPs overseeing the official brochure for the ‘no’ case in the Indigenous Voice to Parliament referendum are refusing to say whether it will include an inflammatory claim by Senator Pauline Hanson debunked as a falsehood by experts.

The clash over the issue puts two leading campaigners on the ‘no’ side of the debate on a collision course over a critical piece of public information about the referendum – but one that is not legally required to be accurate.

There are less than two weeks remaining for the official ‘yes’ and ‘no’ cases for the Indigenous Voice referendum to finalise the wording of an official information pamphlet to be distributed to all Australian households.

Ensuring that the hard-copy pamphlet would be sent to 12 million households was a key demand made by Opposition Leader Peter Dutton during negotiations over a recently passed bill allowing for the referendum to be held.

Politicians who voted in favour of a recently passed constitutional alteration bill can contribute to the ‘yes’ essay and vice versa; their contents must be authorised by a majority on either side.

Essay excerpts

Senator Hanson is pushing for the inclusion of excerpts from her own 2000-word essay on the subject.

It alleges that the Voice would “effectively undo the great achievement of the 1967 referendum” which led to Indigenous Australians being counted as people in the Census for the first time by undermining constitutional equality.

The Voice would, the essay claims “be a vehicle for constant litigation in the High Court, resulting in multiple constitutional crises”.

Changes flowing from the referendum, it claims, could lead to “hundreds of millions” of dollars in legal settlements, the cost of which would be borne by “non-Indigenous taxpayers”.

“As these cases are being decided, Parliament and the executive government will be left effectively powerless and constantly subordinate to the Voice,” the essay asserts.

That claim is made despite the proposed amendment to the Constitution including a clause that would explicitly reaffirm the status of the Voice, an advisory body, as subordinate to the Parliament.

Legal experts agree that the Voice, if established, would not come at the expense of the sovereignty of the Parliament.

Neither of the chairs of the parliamentary group producing the ‘no’ case, Coalition senators Jacinta Nampijinpa Price and Paul Scarr, said on Tuesday night whether Ms Hanson’s contribution could be included.

The issue could potentially create a fissure in the ‘no’ camp after Nationals Leader David Littleproud – who is Ms Price’s party leader – previously said he did not support the inclusion of contributions from Ms Hanson of that nature.

“I’m committed to making sure that not only the tone but also the pamphlets [are] factual,” he said last month.

Despite carrying the official status of public information material for a referendum, there is no obligation on the material contained within the pamphlet to be accurate.

Senator Lidia Thorpe, who rejects the Voice on the grounds that it is an unacceptable compromise of Indigenous sovereignty, has meanwhile been pushing for the inclusion of a progressive case against the referendum in the official pamphlet.

Senator Hanson has been outspoken in her opposition to those arguments being carried in the publication.