"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 ..."
He said Ms Collins had disputed the version of her role set out by Slater in the email. Journalists mentioned in the same email had also rejected what he said about them.
The SFO wound up its criminal investigation against Hanover last year, saying it had found nothing to meet its threshold to pursue a prosecution.
About 16,000 people with investments totalling in excess of $500 million lost most of their money following the failure of Hanover and related companies, and the sale of assets to Allied Farmers.
Key to outline inquiry into Collins and blogger
Prime Minister John Key is expected today to set out the shape of an inquiry into Judith Collins' dealings with blogger Cameron Slater as Labour leader David Cunliffe calls for a full commission of inquiry into the fallout from the Dirty Politics claims.
Right-wing commentator Matthew Hooton has suggested the police should step in also.
The inquiry follows emails released yesterday suggesting Slater and blogger Cathy Odgers were being paid by connections close to Mark Hotchin to attack Serious Fraud Office head Adam Feeley in 2011.
Mr Key announced the inquiry after he was shown an email in which Slater suggested Ms Collins and he were sharing information about Mr Feeley. Ms Collins has denied that but resigned as minister while the matter was investigated.
Slater has also laid a complaint with the Privacy Commissioner over Mr Key's decision to release that email publicly. The PM said the email should be in the public domain in the interests of accountability over Ms Collins' resignation.
Mr Cunliffe also called for the police to seize all information on the computers in Ms Collins' office.
Mr Key said Ms Collins was a "thoroughly professional person" and would comply with any inquiry.
Mr Cunliffe described the latest allegations as "as bad as politics gets".
Mr Key did not believe the police force was the appropriate body to investigate because it was a matter of the relationship between a minister and a chief executive.
State Services Commissioner Iain Rennie said he was concerned by the allegations but an initial investigation had found no evidence that Ms Collins had undermined Mr Feeley.
New Zealand First leader Winston Peters said an independent inquiry was required.
Staff, but not PM, to appear before inquiry
Several staff members from Prime Minister John Key's office have been called to give evidence to an inquiry by the Inspector-General of Intelligence and Security - but Labour MP Phil Goff says Mr Key's own absence would "dramatically weaken" the credibility of the investigation.
Watch: Dirty politics: PM's office receives subpoena
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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