Government officials tendered advice on a controversial plan to entrench part of the Three Waters legislation nearly a month before the provision was voted on by Parliament and passed.

Local Government Minister Nanaia Mahuta received advice from officials on October 25 on a proposal to make it more difficult to privatise Three Waters assets.

A response to a Written Parliamentary Question from National’s Chris Bishop said this was the earliest advice officials gave on a Green Party amendment to entrench the anti-privatisation parts of the Three Waters reform.

The controversial move was criticised by constitutional experts and dubbed a “mistake” by the Government, before being repealed during the last sitting block.

National argues this is further evidence of Mahuta’s defiance of the Prime Minister, and repeated calls for her to be sacked.

A spokesperson for Mahuta said this did not mean officials were working on an entrenchment policy. Instead, they were providing advice about a letter Green MP Eugenie Sage had sent to Mahuta on October 20 about Three Waters proposals - although this letter included a proposal relating to what would become the entrenchment amendment, or supplementary order paper (SOP).

“Officials were not working on advice on the Greens SOP in October,” the spokesperson said.

“Officials were providing advice to the minister about a letter received from Eugenie Sage. The letter canvassed a wide range of changes the Green MP wanted to see made to the bill.

“For avoidance of doubt, the minister does not accept the claim she was ‘working with officials on entrenchment.’”

In her response to Bishop, Mahuta said that earliest advice was about proposals put up by Sage regarding preventing privatisation.

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“Officials noted that Hon Sage’s proposals around preventing privatisation may be progressed through a supplementary order paper and the Government would need to decide whether to support it,” Mahuta said.

The written questions revealed a timeline of what advice Mahuta had received on the amendment put forward by Sage.

“Cabinet agreed in May 2022 to not pursue entrenchment in the Three Waters legislation, but it’s now extremely clear that Ms Mahuta blatantly ignored this and carried on with her desire to put entrenchment in the legislation anyway,” Bishop said.

Officials gave advice on Sage’s letter on October 25, a fortnight before the proposal was published in a select committee report, nearly a month before she took the proposal to caucus on November 22, and before its vote on November 23.

Officials also provided advice to Mahuta on November 22.

“The precise text of the SOP became known when it was released on 22nd November, after the caucus meeting had concluded. On its release officials raised issues with the scope and wording of the SOP and provided advice to the Minister,” Mahuta’s spokesperson said.

Eugenie Sage has said the entrenchment was aimed to protect water from being privatised. Image / Rod Emmerson

Bishop said the timeline was “damning”, and undermined the Government’s argument that the entrenchment had been a “mistake”.

“The Government has tried to make out as if Labour’s decision to support the entrenchment SOP from the Greens was simply a mistake, made almost accidentally,” Bishop said.

“This is now strike three against Ms Mahuta. The first strike was the disclosure that Cabinet had explicitly agreed not to pursue entrenchment, which she then voted for anyway. The second was her refusal to consult Justice Minister Kiri Allan about the entrenchment issue, in breach of the Cabinet Manual. Now we’ve learned she had actually been working away on entrenchment for weeks,” Bishop said.

“Ms Mahuta seems to regard Cabinet decisions as mere inconveniences to be ignored when she chooses. The Prime Minister needs to show some leadership, pull Ms Mahuta into line and sack her.”

The timeline raised questions about why her party’s caucus seemed almost entirely unaware of the Green Party’s plan to entrench part of the legislation, despite the minister receiving advice from officials on the idea two weeks before it was made public in the select committee report and almost a month before Mahuta took the idea to caucus.

Labour has been opaque about how it came to vote for a proposal to entrench anti-privatisation parts of the Three Waters legislation last month.

In April, the Government proposed entrenching the provision with at a threshold of 75 per cent, meaning it would take 75 per cent of MPs or a successful referendum to repeal. But this would have required the support of the National Party, which refused to back it on the grounds it opposed Three Waters outright.

With this avenue scuppered, Cabinet resolved not to pursue entrenchment.

The Greens, however, came up with a proposal to entrench the provision at a threshold of 60 per cent - something Labour and the Greens could do on their own.

This was released on November 11, and the proposal was passed on November 23.

Since then, questions have been asked about whether Mahuta made Labour’s caucus fully aware of what they would vote on.

Comments from Prime Minister Jacinda Ardern and Leader of the House Chris Hipkins suggested that the principle of entrenchment at 75 per cent was discussed at caucus - a proposal that was doomed to fail. However, it appears the proposal to entrench at 60 per cent - which was guaranteed to succeed if Labour voted for it - was not discussed, despite Mahuta being aware this was the Greens’ proposal.

 “I’ve also discussed and pointed out that entrenchment is generally understood to be a threshold of 75 per cent,” Ardern said, at the time.

“We took a view on the principle of ensuring that a public asset like water is absolutely protected from privatisation.

“What came before Parliament was a more novel approach.”

Beyond this, Ardern and MPs have said that all caucus discussions are confidential. Mahuta’s spokesperson repeated that on Monday and would not elaborate on how many Labour MPs knew the full extent of what the Greens were proposing.