Two members of the Glenn Inquiry have quit in the latest blow to Sir Owen Glenn's campaign aimed at tackling child abuse and domestic violence.
Sir Owen withdrew his application to become an ambassador for the White Ribbon campaign against violence on Tuesday after revelations of an historical abuse case.
The move follows accusations in 2002 that Sir Owen physically abused a woman in Hawaii, where he entered a plea of no contest. This meant everyone involved in the case agreed to some extent about what happened, without Sir Owen having to plead guilty. The case was dismissed in 2004.
White Ribbon chairperson and former Family Court Chief Judge Peter Boshier says the public spectacle over the case has damaged the campaign.
On Tuesday afternoon, Neville Robertson and Anton Blank resigned as advisers to the Glenn Inquiry.
Professor Robertson, from Waikato University, told Radio New Zealand's Checkpoint programme his resignation is not so much to do with the allegation, but more because he had become increasingly frustrated by the inquiry's lack of transparency.
"It was very clear to us when we signed up that the foundational values of the inquiry were honesty, transparency and integrity. And when you think about the nature of abuse, it's not hard to understand why those values are incredibly important."
Professor Robertson said the inquiry has 35 members and about half have quit, while the rest are considering it. He said its future doesn't look promising. "My view is that it is unlikely to achieve its mission, but it's up to the people who remain in the inquiry to see if they can make it work."
Anton Blake, executive director of Maori welfare organisation Ririki, said his decision to leave was made before the allegation against Sir Owen was revealed.
In a letter to Judge Boshier released on Tuesday, Sir Owen said the media coverage of his nomination was distracting attention from the White Ribbon campaign.
Sir Owen said he is living violence-free has no history of violence towards women or children. Judge Boshier said he appreciates Sir Owen putting the reputation and work of the White Ribbon campaign at the forefront of his decision.
On Monday, the chair of an inquiry into family violence founded by Sir Owen said he believed the revelation of the 2002 accusation had come from someone close to the inquiry who appeared to be running a campaign against it.
Glenn Inquiry chair Bill Wilson said he was confident there was no truth to the abuse allegation and the inquiry remains on track.
The executive director of anti-violence organisation Shine, Jane Drumm, said Sir Owen should have been open about the allegation, even if it was false.