National leader Bill English launched a stinging attack on Prime Minister Helen Clark today, saying her handling of the "paintergate" affair meant she could not be trusted.
Mr English said a police report into Miss Clark signing an artwork for charity that was painted by someone else had "shocked" him.
The prime minister's staff reacted quickly to the speech, telling journalists they had a legal opinion that a number of Mr English's comments and assertions, made at the National Party conference in Wellington, were defamatory.
The police inquiry into the painting affair found the "secret buyer" of the painting, after its existence became public, had given it to a member of Miss Clark's Auckland staff.
That staff member told police she had asked Miss Clark what she might do with the painting, then burnt it after Miss Clark told her to "do with it as she liked".
Police said there was a "lack of evidence to prove any intent to obstruct justice" by any staff member or by Miss Clark.
Mr English said in his speech: "A staff member of Helen Clark walks into her office to get advice about what to do with the painting ... She (Miss Clark) did not say anything (to police) about the fact a staff member had consulted her about the painting and about what to do about it."
Speaking to journalists after the speech, Mr English said: "The police themselves said Helen Clark left those events out of her statement. That is the judgment of the police who did a thorough investigation and I am saying that is slippery."
In his closing address to the National Party conference, Mr English said Labour's entire campaign was based on "trust in one person (Miss Clark)" and Labour could not be trusted on education, law and order, health and taxes.
Mr English urged wavering National party supporters to vote for what they believed in and not tactically to keep the Greens out of government. He said those voters who trusted Miss Clark to be moderate and fair were misguided.
He said Labour did not want to end the secondary school teachers' dispute: "I say to parents get political, because that's the only thing that will solve that problem. Labour won't. They have decided not to. Parents must express their anger through their vote."
The poor financial state of the health system was being covered up: "I know what those numbers mean. They mean cuts, big cuts for real people for people who trusted Helen Clark ... they should tell us the truth on health," Mr English claimed.
Mr English accused Labour of not telling the truth about plans to raise taxes and how the new sentencing laws were soft on crime.
Miss Clark said through a spokesman that the speech was "an outrageous outburst by a desperate man whose party is in free-fall. It is simply gutter politics".
Mr English's speech came as senior party strategists worked on how to bring back supporters to the fold.
Party polling has up to 12 percentage points of those who said they would vote Labour backing National policies - particularly on law and order, Treaty of Waitangi issues, health and education - but saying they still won't vote for the party.
The strategists believe the so-called "soft vote" is going to Labour to ensure that party gets a majority and keeps the Greens out of government. Those potential National voters also trust Miss Clark to be a moderating influence in government.
In his speech, Mr English said those who did not vote for what they believed in would be very sorry if a Labour or Labour-led government took office after election day.
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