Liberal senator Jacinta Nampijinpa Price has come under fire in the Federal Court witness box over a press release from her office that sparked a defamation case, including being grilled about whether she knows “what a vote is”.

Price is defending the defamation suit filed against her by Central Land Council chief executive Les Turner. The trial, estimated to run for at least seven days, started in Darwin on Monday.

The opening line of the press release, sent by Price’s office in July last year to almost 2000 journalists, said that a “motion of no confidence was moved last week in relation to the CEO of the Central Land Council”. Turner was not named, but there is no dispute that it identified him.

The press release said: “Through last week’s vote, a majority of Central Land Council members showed their support for the dismissal of the CEO due to unprofessional conduct.”

It said the motion was “unsuccessful” but that it had been “backed by the Central Land Council chair Matt Palmer”.

Price appeared for the first time in the witness box on Friday afternoon and came under intense questioning from Turner’s barrister, Sue Chrysanthou, SC.

“As you sit here now, do you say you believe it was true that there was a vote about the dismissal of my client?” Chrysanthou said.

“That’s what I believed, this is what Mr Palmer had told me,” Price said.

Chrysanthou asked if she still believed this, having heard the evidence in the trial and read documents in the case.

Price said she believed Palmer had “claimed he had the support of individuals who were the vast majority of those that attended” and “in their minds had voted”.

“Do you know what a vote is?” Chrysanthou asked.

“I do,” Price said.

Chrysanthou said: “You’re a politician. You understand what voting is, correct? What’s your understanding of what a vote is?

“You accept now, as you sit here, that there was no vote of the Central Land Council to dismiss my client?”

Price replied: “I accept there was no formal vote.”

Asked if she accepted there was “no vote at all” based on the ordinary English meaning of the word vote, Price said: “I accept.”

Asked how it made sense to her that a majority of CLC members could have voted to dismiss Turner but the motion had failed, Price suggested there could have been “other reasons why” that happened.

In documents filed in court, Turner says the media release conveyed a number of false and defamatory claims about him, including that he “no longer had the support of the majority of Central Land Council members because of his unprofessional behaviour in that role”.

Price has admitted this claim was conveyed, and is not seeking to prove it was true. Instead, she is seeking to rely on the defence of qualified privilege, which protects some publications of public interest where a publisher acted reasonably. Reasonableness is expected to be the key battleground in the case.

Peter Gray, SC, acting for Price, submitted to the court that the failure to contact Turner before issuing the media release did not indicate a lack of reasonableness.

“Did you care to ask him what his response was? Did you not think that would be a fair thing to do?” Chrysanthou asked.

“Not necessarily,” Price said.

Price has said the litigation could “cost me my seat in parliament” if she lost and was bankrupted because she was unable to pay damages and legal costs.

Under section 44 of the Australian Constitution, members who are undischarged bankrupts or who are insolvent are ineligible to sit in parliament.

Price started a crowdfunding campaign for her legal bills earlier this year. She disclosed in the parliamentary register of interests in September that Australia’s richest person, Gina Rinehart, had made a contribution to the legal fund via her company Hancock Prospecting. Price has confirmed she met her fundraising goal of $320,000.

Price said during her evidence on Friday: “I only publish things that I believe to be true.”

Chrysanthou rejoined: “Are you good at admitting publicly when you’re wrong, senator?”

The trial continues on Monday.

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