Family First director Bob McCoskrie said he was "surprised" to hear allegations that Conservative Party leader Colin Craig had sexually harassed his press secretary.
McCoskrie has been called as a witness for Craig at his defamation trial in the High Court at Auckland today.
He has told the jury that Craig spoke to him early last year about MacGregor.
McCoskrie was a supporter of some of the Conservative Party's policies because of his role in an organisation that stood for family values. He was not a party member or official supporter.
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"Colin Craig confided in me that Rachel had made a sexual harassment claim against him," he said.
"In May 2015 Colin spoke to me again, advising me that he had settled the matter confidentially.
"I told Colin I thought this was the best outcome for all parties concerned."
Soon after that McCoskrie said he was contacted by Jordan Williams, a friend of MacGregor who was also a supporter of the party.
"Jordan told me he believed Colin had committed serious sexual harassment including sending sext messages," McCoskrie told the court.
He said he "demanded concrete evidence" and during a video call Williams tried to show him copies of what he said were poems Craig had written and sent to MacGregor.
"I asked for copies so I could challenge Colin on them. I never received them," he said.
"I was surprised by Jordan's allegation and thought they were very serious."
McCoskrie said he repeatedly asked Williams for proof, particularly around the alleged sex text where Craig purportedly spoke about dreaming that he had slept between his press secretary's naked legs.
He thought he would be the best person to make Craig "face facts" if the message and poems had been sent.
"I don't think he's going to listen to anyone else," McCoskrie said in a text message to Williams.
He said he never got the proof he had asked Williams for and effectively told the man to "put up or shut up".
"I wanted hard concrete evidence," he said.
Williams' lawyer Peter McKnight asked McCoskrie what he thought of the letters and poems Craig sent to MacGregor, a much younger woman and employee.
"Inappropriate, but I would qualify that with, depends what's coming back in the opposite direction," he said.
What McCoskrie thought of Dirty Politics
McCoskrie told the jury what he thought of Craig's attempt to address the allegations by publishing a pamphlet called Dirty Politics and Hidden Agendas.
In the publication Craig said Williams was among three "schemers" who had spread false accusations about him.
McCoskrie said he had not seen the pamphlet before it was released but understood Craig's motivation to create it.
"I formed the view that Colin was doing it because it was the best way to clear his name and respond to the people who were trying to take him down," McCoskrie said.
"Everyone has a right of response and if this was the way he has to do it, this was the way he has to do it.
"It was pretty clear to everyone that there was an attempt to show Colin in a negative light. It was serious allegations," McCoskrie said.
After he finished giving evidence, and being cross examined and dismissed, McCoskrie was recalled to the witness stand.
McKnight questioned McCoskrie on when he first saw the Dirty Politics pamphlet.
McCoskrie said: "I did not see the booklet in any form before it was released publicly".
McKnight said in the morning tea break evidence had been produced that McCoskrie had been sent a copy of Dirty Politics in an email by Craig a day before he released it.
"There's an email from Mr Craig to you on 28 July 2015 and he says there 'hi Bob, well it's all go, here for you to read'.
A press statement about the pamphlet was also attached.
The actual release of the pamphlet was July 29.
McKnight asked McCoskrie if he recalled the email from Craig and whether he had read the pamphlet.
He replied that if he had received that email, he did not recall it, and maintained that he had not read the pamphlet in any form before its public release.
He explained that he responded or at least acknowledged he had received emails with a reply to the sender as soon as he had read it.
He replied to Craig's email after 4pm on July 29.
Following McCoskrie's evidence Craig's lawyers called Sensible Sentencing Trust founder Garth McVicar, who was a Conservative Party candidate in the 2014 general election.
McVicar said he was contacted by Williams after Craig had stepped down as leader following MacGregor's resignation.
He said Williams offered to show him information about Craig.
"I said 'no thanks',' McVicar said.
He told Williams he wanted to see the information before he made a decision on what to do with or about it.
He then informed Craig.
Why is Colin Craig on trial?
The defamation trial unfolded after Craig's press secretary, Rachel MacGregor, resigned suddenly just 48 hours before the 2014 general election.
The resignation was high profile and there was much speculation about why she left.
Weeks later MacGregor turned to Williams for support, and told him she had made a complaint to the Human Rights Commission alleging that Craig had sexually harassed her.
She shared letters and poems the politician had sent her. Williams then revealed the details to other Conservative Party members.
When Craig found out he publicly claimed Williams was part of a group of "culprits" determined to have him removed as party leader through a "campaign" of "false accusations".
Williams then filed defamation proceedings in the High Court, saying he did not lie about Craig.
The trial continues.