The highly secretive group, which boasts 40,000 members worldwide – many based in New Zealand and Australia – has been accused of underhanded campaigning against the Greens at the 2004 federal election and subsequent state polls.
The group came under the spotlight when NZ Prime Minister Helen Clark accused it of running a smear campaign against her and fuelling rumours her husband was gay.
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The outcry that followed prompted NZ Opposition Leader Don Brash to publicly sever ties with its members.
Brethren members eschew contact with the modern world, and are barred from going to university or having TVs, radios, personal computers and mobile phones.
Mr Howard admitted for the first time he had met with representatives of the sect, but said he had talked to many other fanatical groups in his time as a politician.
“I’ve met a lot more fanatical people in my life than the Exclusive Brethren,” he said.
“It’s a free country. They are not breaking the law (and), like any other group, they are entitled to put their views to the government.”
The prime minister said he did not have a problem with them.
“We don’t (run) a police state in this country and, unless people are an unlawful organisation, they are entitled to meet with the government.”
Australian Greens senator Christine Milne said the sect’s involvement in politics lacked transparency and called on Mr Howard to reveal details of his discussions with its members.
“It’s entirely appropriate that politicians have meetings with people from a whole range of groups,” she said.
“What we don’t support is secretive and shady dealings.”
Senator Milne said the public had a right to know whether Mr Howard had discussed school funding, industrial relations policies or financial support for coalition parties at elections.
“The community has a right to expect that they will know who is trying to influence the outcome of elections,” she said.
“The Exclusive Brethren has deliberately set out … to fly underneath the radar.”
One Exclusive Brethren member could potentially donate up to $90,000 to the Liberal Party in $10,000 instalments to each of its state, territory and federal branches without the public ever knowing they had under controversial electoral laws passed this year, Senator Milne said.
She was also suspicious about the length of time the Department of the Prime Minister and Cabinet took to respond to Greens’ questions asked in Senate Estimates hearings in October last year.
In its response, the department said the prime minister had met with members of Exclusive Brethren, but refused to reveal the details, saying they were confidential.
The Brethren’s leader, Bruce Hales, lives in Mr Howard’s Sydney seat of Bennelong where the group campaigned against Greens’ candidate Andrew Wilkie at the 2004 federal election.
Victorian Nationals leader Peter Ryan has reportedly disassociated himself from the Exclusive Brethren after last week saying he would welcome its assistance campaigning against the Greens and Labor in November’s state election.
“The publicity surrounding the organisation carries with it the strong suggestion of a series of initiatives that don’t sit well with me,” he told online news service Crikey.
“There would appear to be an over-arching control of family members and young people in a way which seems to me to be excessive.”
Former members of the sect have alleged on ABC Television’s Four Corners program that large sums of cash have been transported by members across international borders and have accused the group of hushing up child abuse.