Former Serious Fraud Office boss Adam Feeley says he would not have briefed ministers on investigations if he had had any suspicion that information was being leaked to others.
Mr Feeley spoke to the Herald after right-wing commentator Matthew Hooton said that if there was any suggestion senior government figures were passing information on the Hanover investigation to Whale Oil blogger Cameron Slater in 2011, it would be a very serious matter.
Asked whether he was ever concerned that information he had given to Judith Collins or her officials might have found its way to Hanover director Mark Hotchin or the company's lawyers, Mr Feeley refused to comment directly on the case but confirmed he did "periodically give ministers indications of where particular investigations were going".
"We often had concerns that when we interviewed people, there had been some form of disclosure by some parties, but that wasn't specific to ministers. That related more to people involved in cases. Would I have disclosed information to any minister if I had concerns about the security of that information? No, of course I wouldn't."
Ms Collins resigned from the Cabinet on Saturday after an email was revealed in which her name was linked to a smear campaign against Mr Feeley run by Slater and other parties linked to Mr Hotchin. He was at the time under investigation by the SFO.
Ms Collins has denied being involved in any smear campaign.
Ms Collins' resignation was prompted by Prime Minister John Key's release of the email from Slater in which the blogger claimed she had been "gunning" for Mr Feeley while she was minister in charge of the SFO.
Former SFO general manager Simon McArley told 3 News he believed the SFO was targeted in a smear campaign during its Hanover inquiry.
Read more of the Herald's coverage:
• Calls for a full commission of inquiry
• The money men and how they toppled Collins
• Commissioner concerned by allegations
• Gallery: Collins in cartoons
• I'm the victim of a smear campaign: Judith Collins resigns
• Resignation reaction: 'Too little, too late'
• The email that brought down Judith Collins
• Collins resigns: Blogger backs mate
• Collins resigns: Jared Savage and Fran O'Sullivan respond
The Herald now understands the email that Mr Key released on Saturday was forwarded to a Beehive staffer by Slater's friend Cathy Odgers, who blogged under the name Cactus Kate.
Other emails between Odgers, Slater and public relations consultant Carrick Graham released to media yesterday suggest the trio also plotted to work against another regulatory body, the Financial Markets Authority.
In one email, released by a hacker who claims to have taken the messages from Slater's computer, Slater says, "Let us go to war on the Financial Markets Authority, Hotchin stays quiet, we do the hitting".
Labour leader David Cunliffe said that if the allegations against Ms Collins were true, "they would show corruption which goes to the heart of the Government".
"This is John Key's network, this is not just about Judith Collins.
"This is a much bigger, deeper issue. Something is rotten in the heart of the National Government."
Mr Key said Mr Cunliffe was "trying to create a political smear ..."
Mr Goff, blogger Cameron Slater and staff from the Prime Minister's office have all been summoned to give evidence to the inquiry into an Official Information Act release from former Security Intelligence Service director Warren Tucker to Slater.
Mr Key initially said he had been summoned by Inspector-General Cheryl Gwyn but his office later said several of his staff had been asked to appear, but not Mr Key himself.
"There was no indication in the letter that the Prime Minister would be called personally and the Prime Minister's office is not aware that would be the case."
Mr Goff said he was surprised. "He is a key player in this. To not have the Prime Minister give evidence under oath would dramatically weaken the inquiry."
At the point he believed he had been summoned, Mr Key said he would have been disappointed if he had not been called.
"If it wasn't being done this way, frankly, I'd be pretty disappointed because we want to make sure the facts are out there and not some claims from the Opposition that this has been a whitewash."
The release showed Mr Tucker had briefed Mr Goff on Israeli backpackers the SIS had initially suspected were spies - a briefing Mr Goff did not recall. The issue arose again after claims in the Dirty Politics book that the decision to release it was politically motivated and Slater was tipped off in advance about the contents and timing of the release.
Mr Goff said he would appear on September 8. It is not known which staff from the Prime Minister's office have been called and Mr Key has refused to say who Mr Tucker had briefed about the Official Information Act request for details of the briefing.
Mr Goff said Jason Ede and Mr Key's chief of staff, Wayne Eagleson, should both have to give evidence.
Slater confirmed he had been called to give evidence on September 11 - just nine days before the election.
Mr Key has maintained he was not personally told of the OIA request or the decision to release it by Mr Tucker, but his office was told under the "no surprises" policy. Mr Key was on holiday in Maui at the time, and is happy to release his phone records.
- Claire Trevett
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