Labour tried to turn the screws on John Key yesterday after he said Rodney Hide had acted to a "high ethical standard", despite being aware of David Garrett's past offences and bringing him into Parliament anyway.

Mr Hide's leadership of the Act Party has been under attack since Mr Garrett quit Act last week after it was revealed he had used a dead child's identity to obtain a false passport.

He was granted permanent name suppression, which was later lifted.

Opposition leader Phil Goff used the rules of the Cabinet Manual to attack Mr Key in the House yesterday about his continued support of the Act leader, who as a minister is accountable to the Prime Minister.

The manual states that the ministers are expected to "behave in a way that upholds, and is seen to uphold, the highest ethical standards" in their ministerial, political and personal capacities.

When asked if he thought his ministers had behaved according to the manual, Mr Key said: "Mr Hide has carried out his affairs in a personal and private capacity to a high ethical standard, but I am not responsible for who he might hire as an MP."

Following questions from Mr Hide referring to an incident involving former Prime Minister Helen Clark, Mr Key said he thought it was improper for a minister to sign a painting they did not paint and then have it destroyed before the matter could be investigated.

Mr Garrett did not return calls yesterday, but he told Radio New Zealand that he would resign from Parliament today, which would allow Hilary Calvert, the next on Act's list, to enter Parliament. He has been interviewed for the Truth Weekender, out today, in which he reportedly talked about the "dark forces" within Act, and the "thrill" of obtaining the false passport.

He also took a shot at Act MP Heather Roy and her former adviser Simon Ewing-Jarvie, who has leaked material to media to damage Mr Hide, and described the whole ordeal as "bloody awful".

In the debate after question time, Mr Goff said Mr Key should strip Act of its ministerial portfolios.

"The Prime Minister absolutely stunned this house and the country by defending Rodney Hide's cover-up of the theft of a dead child's identity as being ethical," Mr Goff said.

"There will be no sympathy among ordinary Kiwis for a Prime Minister prepared to defend the cover-up of an appalling crime."

Law and order spokesman Clayton Cosgrove called Sensible Sentencing Trust spokesman Garth McVicar a hypocrite for supporting Mr Garrett's name suppression request.

"Did those gentlemen ever consider ... that they gagged a 93-year-old woman and her family from ever speaking out?" he said.

Ms Calvert, 55, who is expected to replace Mr Garrett, has had training as a couples counsellor. "Who knows, that might be very helpful," she said yesterday.