National's crisis over the leak of Covid-19 patient details deepened yesterday when senior frontbench MP Michael Woodhouse admitted he was involved.
The Government has criticised National's handling of the scandal, but party leader Todd Muller believes it was "well-managed and transparent".
Muller said he learned on Tuesday Woodhouse had been sent patient records, but believed it was a "distinctly different issue" from Hamish Walker, whose career is now over.
Walker leaked the information, but Woodhouse did nothing with it, Muller said.
Walker admitted on Tuesday evening he was behind the leak of patient records to media. His source was former party president Michelle Boag.
Woodhouse revealed yesterday he told Muller that he'd also been sent details by Boag.
But on Thursday Muller was specifically asked if he'd checked whether Woodhouse had received similar information.
Muller said: "No. It's very clear from our perspective that there is a conversation that's occurred or a connection that's occurred between Michelle Boag and Hamish Walker."
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Muller told the Weekend Herald he believed the information Walker leaked was different to what Woodhouse had received so they were separate issues.
"From my perspective what Hamish did was unacceptable and that was well-canvassed. With respect to Michael, when I got that question I was looking at it through the lens of the information that Hamish received.
However, he acknowledged he could have answered the question better.
"I could have put it clearer but that was the distinction in my mind when the reporter asked the question."
Muller rejected it was a lie by omission.
"I was the one that made sure that we made [Walker's confession] public on Tuesday. Actually, from my perspective, we have been well-managed and transparent about it."
Yesterday, Boag quit the National Party after dedicating almost 50 years of her professional and personal life to supporting it.
"Unfortunately this passion has put me on a self-destructive path."
Yesterday Boag admitted she also sent patient details to Woodhouse because it was her "distorted view" that sharing it would help the National Party.
"The last few days have underscored for me the unhealthy relationship I have developed with politics."
Boag said the patient data was sent to her company email address because she was the acting chief executive of the Auckland Rescue Helicopter Trust. The trust later said she shouldn't have had access to patient information in that role.
Woodhouse said that before sending him the information last month, Boag called to say she "had some information around Covid that would be helpful to me" and asked for his private email address.
He said he opened one email, saw it was patient information and "clearly there was nothing that I could benefit from and I did not use it".
Boag sent him three more emails between June 21 and 25. Woodhouse said he didn't open them as he was away from his Dunedin electorate office.
Last Saturday, the Weekend Herald revealed details of the then 18 active Covid-19 cases had been leaked.
Woodhouse said after reading news of the leak, not knowing it was Walker, he texted Boag to say: "I'm sure I don't have to say this but I am absolutely not the source of the leak.
"She contacted me to say, 'I know you're not the source of the leak because the information is different'."
Woodhouse said it "never crossed my mind" Boag was behind the publicised leak as he understood the patient information was widely circulated around various health agencies.
On Saturday, Woodhouse condemned the leak, saying: "This is unconscionable and unacceptable that those suffering from the incredibly dangerous virus now have to suffer further with their private details being leaked."
On Monday, State Services Minister Chris Hipkins launched a powerful inquiry headed by Michael Heron, QC, promising to uncover "exactly who" was responsible.
That same day Walker told Muller he was the leaker but later sent him a legal letter asking not to name him, citing privacy.
Muller got his own legal advice and pushed forward with getting Walker to publicly confess. On Tuesday evening, Walker took responsibility for the leak.
At the same time, Boag revealed she was his source.
Woodhouse said after the pair admitted their actions, he gave Muller "a quick call to say I think there could be another dimension to this story".
"He asked me to talk to Amy Adams in the morning about that, which I did."
He deleted the emails from Boag that evening. He and Boag say they have contacted Heron and will cooperate with the inquiry.
Muller said he stood by Woodhouse "100 per cent".
"The critical error of misjudgment was Hamish Walker's in terms of leaking that information."
Muller said he was disappointed Woodhouse hadn't told him sooner "but it needs to be put in the context that he obviously didn't do anything with it".
Muller has not asked all his MPs whether they'd also received sensitive information from Boag.
He said he'd "reinforced" to his caucus his expectations of them and that if they receive highly sensitive information like that, they should elevate it to the leadership.
National deputy leader Nikki Kaye was also told Woodhouse had been sent patient information.
She was asked if National should have front-footed that and said: "I think it's really important to work through a process and understanding what the information was part of that."
Kaye said she'd not been sent any confidential information from Boag, but they were friends and so was "very sad" about her quitting the party.
Hipkins was critical of how the National Party handled the leak and said Muller and Woodhouse had made "very strong comments" when it was clear they knew how it came to be released.
"It's absolutely legitimate to call out if there has been a failure of information handling.
"It is not legitimate to release that information or to sit on that information and not do anything about it."
Walker stood down from re-election in his Clutha-Southland seat after admitting he leaked patient details to media.
He did it after being called racist by the Government for claiming the active cases were coming from "India, Pakistan and Korea".
Walker believed sending evidence of their names would prove his claim.