Labour Party president Mike Williams had shown "poor judgment" in agreeing Labour Party canvassers could hand out government leaflets, Prime Minister Helen Clark said today.

"This was a not-so-bright idea which came off the floor at a workshop, I understand, and the not-so-bright idea has been thrown off the ninth floor of the Beehive," Miss Clark said today.

Labour held its congress at the weekend and in a closed session on the party's election strategy, run by Mr Williams, delegates were advised to distribute pamphlets on KiwiSaver produced by the Inland Revenue Department and on Working for Families produced by Work and Income.

They were also advised to tell voters when handing out the pamphlets that National voted against both measures, the New Zealand Herald reported.

When a delegate raised using government leaflets, Mr Williams reportedly felt it was a great idea.

But Miss Clark said he had shown "poor judgment" in this case.

"... as Mike Williams said in his speech on Friday night, no one dies wondering what I think about things and he was the beneficiary of such advice again this morning," she said.

Mr Williams was one of her oldest friends and a very diligent worker for the party "but he doesn't always get things right".

Distributing Government department material explaining how policies work remains lawful under the Electoral Finance Act.

However, if it is directly tied to political campaigns the move could be seen as inappropriate use of Government publicity.

National Party leader John Key today said he was not surprised about the move, as Labour's goal in passing the Act was to silence critics, while at the same time allowing it to use the resources of Government to push its own message.

But Miss Clark said government leaflets were not campaign material and would not be used as such.

"I've said that under no circumstances should canvassers be handing out government leaflets."

Asked whether such action broke any laws, Miss Clark replied that she just did not think it appropriate.

Electorate offices for MPs from all parties should, however, stock information about things constituents were entitled to.

Labour has already breached the law by distributing a taxpayer-funded pamphlet titled "We're Making a Difference," which the Electoral Commission has deemed election advertising.

The congress workshops follow general confusion among the parties over the Act's provisions and just how wide they stretch.

In a sign Labour is highly conscious of avoiding a second breach, printed material handed out at open workshops at the weekend congress carried a disclaimer that they were for party members and not for redistribution.

National has said it will mount a series of legal challenges to decisions made under the Act.

It is seeking a judicial review of the Electoral Commission's decision not to refer Labour's breach of the law to the police.

It is also seeking a review of the commission's decision to allow the Labour-affiliated Engineering Printing and Manufacturing Union (EPMU) to register as a third party and a review of what parliamentarians and parties can spend their taxpayer-funded budgets on.

The union was to register this Thursday, but National is seeking an injunction to prevent that happening until its challenge is heard.

The EPMU said today it would vigorously oppose National's attempt to "silence" its 50,000 members.

The High Court met with lawyers this morning although no firm date had yet been set for a full hearing, it said.

"The union has advised the High Court that it is not affected by a further delay in being registered as a third party and we will co-operate with the court to have the matter heard as soon as possible,' union secretary Andrew Little said.

Meanwhile, Miss Clark said a suggestion by National deputy leader Bill English about the Act was "worthy of consideration".

Mr English wants to amend the new law so that election adverts would not have to carry the home addresses of party officials.