Rachel MacGregor told a colleague she could get "whatever I want" out of Colin Craig, it has been claimed.
Bev Adair-Beets, who took over from Ms MacGregor when she quit as Mr Craig's press secretary two days before the 2014 election, made the claim at the High Court in Auckland today, where Mr Craig is defending a defamation charge.
Ms Adair-Beets told the court she had a private conversation with Ms MacGregor, in which Ms MacGregor said she had a hold over Mr Craig in terms of the money she could get out of him.
She said MacGregor told her: "Watch me, I'll get it. I can get whatever I want."
"She told me she was going to make a stand," said Ms Adair-Beets.
Earlier on Friday, Conservative Party secretary Kevin Stitt says he asked Mr Craig about the contents of his 'Dirty Politics' booklet, but was assured everything in it was true.
Mr Stitt told the court he had no part in making the booklet, which was delivered to households nationwide in July 2015.
"You've made some strong allegations - have you got evidence to back them up?" Mr Stitt said he asked Mr Craig, then leader of the party.
"He assured me he did and I had no reason to question his integrity."
Mr Stitt posted the booklet on the party's website, and sent it to 3480 people on the party's contact database.
"Colin had every right to defend his reputation and Conservative Party supporters had the right to hear the evidence," he told the court.
However, an email written by a party board member Deborah Cunliffe read out to the court said the party's administration - Mr Stitt and Angela Storr - had blatantly misused the party database, suggesting the board sided with Mr Craig, and recommended Mr Stitt be dismissed.
Mr Stitt said he accepted then that Mr Craig was the Conservative Party.
Mr Stitt said Mr Craig told him the booklet was a "true reflection" of what he believed happened. He said Mr Craig was expecting a backlash, but was determined that the truth could be revealed.
"Mr Craig assured me he had evidence and I was prepared to accept that."
But when asked if he had seen that evidence, Mr Stitt replied he had not.
Mr Stitt said the Conservative Party stood for principles and morals, but when asked about a poem Mr Craig had written he said it was "inappropriate" and Craig had gone a "little too far".
Mr Stitt was originally named as a second defendant in the trial because he posted the booklet online for the party's membership to read, but the case against him was dropped in August.
The booklet is still available to read on Mr Craig's website, despite it being at the centre of the defamation trial.
There's no love lost between the head of the Taxpayers' Union Jordan Williams and his political adversary Martyn 'Bomber' Bradbury.
"How does one be complimentary about a venomous spider, I don't like the guy, no," Mr Bradbury says.
Mr Craig invited Mr Bradbury to court to criticise the tactics of Mr Williams and bloggers like Cameron Slater.
"I think that Mr Williams and his friends are political sadists who are a cancer on the body politic of this country," Mr Bradbury says.
In Mr Bradbury's view this was less a trial about Mr Craig's relationship with Ms MacGregor and more about Mr Williams' angry fight with Mr Craig.
The trial is drawing to a close with closing arguments lined up for next week.
The jury expected to be out by Wednesday.