Costly anti-Government leaflet drops throughout the country have been identified as the work of a conservative offshoot of the Brethren faith.
The revelation is a surprise, as the Exclusive Brethren supposedly divorce themselves from worldly matters and do not normally vote.
Exclusive Brethren socialise only with other Exclusive Brethren and eschew technology such as televisions, computers and cellphones.
The anti-Green and anti-Labour leaflets printed by Business Printing Group in Onehunga are estimated to have cost between $30,000 and $40,000. New Zealand Post estimated distribution to major centres alone to cost between $55,000 and $60,000.
The Green Party's own inquiries confirmed the identities of five people listed on the smear pamphlets as Exclusive Brethren.
All are listed in an Exclusive Brethren confidential address book that the party obtained.
Party co-leader Jeanette Fitzsimons said she was shocked to hear that the secretive church had put its membership and financial weight behind the National Party.
"The Exclusive Brethren have the absolute right to campaign for the National Party, but not to tell outright lies and half-truths about Green policy in a bid to get their man to the top.
I do find it strange that a group that claims to be Christian can so easily break one of the Ten Commandments by telling such lies."
Excommunicated church member John Wallis said the foray into politics was due to the church's new leader, Australian Bruce Hales, who took over when his father, John, died. He said Bruce Hales had told members before George W. Bush and Australian PM John Howard were re-elected that if they were not returned to power, "the rapture", or end of the world, would be near.
"They have been very politically active in the last few years since Bruce Hales has been involved."
Church members were typically right wing, he said.
"I'm tipping that they'll actually vote this time in New Zealand, which is something they've never done. I can see it happening ... "
Another excommunicated member said the Brethren's campaign for a change of government started with adverts in major newspapers, with the wording, "Wake Up New Zealand", and letters to the editor denigrating Labour and the Greens.
"They are very right wing and obviously hope that National will get in, and have been active in supporting them."
Stephen Win, who authorised "The Green Delusion" leaflet - which dubbed the Greens as "socially destructive" - is better known by his middle name, Myles, among fellow brethren.
Stephen Myles Win's phone went straight to message service yesterday but he left a message with the Herald later, saying a press release on the matter would be issued today.
The Chief Electoral Officer has been called in to investigate the anti-Greens leaflet, which the party says breaches the Electoral Act.
Election advertising by third parties that does not advocate support for a party or candidate requires only a statement on the advertisement stating the true name and address of the authorising person.
* Cannot eat or drink with, or marry, non-Brethren.
* Cannot live in the same building as anyone who is not in fellowship, including a semi-detached home in which a wall is shared.
* The men are usually self-employed businessmen, and the women fill traditional roles as wives and mothers.
* They number fewer than 2000 in New Zealand, and about 40,000 worldwide.