The Greens promote the idea of transparency, but rolling resignations inside the "toxic" NSW division suggest it is a secretive party and doesn't allow dissent. Conor Duffy writes.

If any other political party began an election year with a series of rolling resignations of senior office bearers decrying a "toxic" culture inside it the news would soon become public.

Yet in the secretive world of the NSW Greens the resignations of four office bearers including the treasurer and party secretary remained hidden until broken by 7.30 late last month.

The dispute centres on a push to professionalise a party that now receives large amounts of public funding and an old guard desperate to retain control.

In the course of investigating this story for 7.30 we contacted many former and current Greens from very junior to senior.

Not one would speak on the record.

Many spoke of their fear of repercussions.

One said:

I've been contacted previously and told we don't tolerate anyone stepping out of line.

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Another said "the party crucifies anyone who speaks on the record" and that secrecy was "deeply entrenched" in the culture.

The Greens have the most restrictive rules around media access to party debates and internal processes.

The office bearers were all members (and some election candidates) of the powerful Committee of Management (COM) which functions like a state executive.

In a previously unpublished resignation letter one party office bearer didn't hold back, decrying:

...the abhorrent and toxic culture that permeates not just this Committee (although we do a very good job of creating, bathing and indulging our own drama), not just the office, not just the Young Greens, but so much of the party which I have engaged with. Never before have I seen people treat people so poorly, with so little regard, with no respect or time or consideration.

As well as the resignation of the four officials, the party's most senior employee Carole Medcalf remains in a serious industrial dispute.

Ms Medcalf declined to speak to 7:30.

Other parties allow former officials and MPs to comment on the party and give voters, via the media, insights into how they function internally.

Political commentator David Burchell from Western Sydney University told 7.30 there is an authoritarian tendency in the NSW branch of the party:

There seems to be a strange part of the culture with the Greens where they view themselves as under attack, they view large parts of the media as their enemies.

The NSW wing of the party is separate from the federal party and the history and culture of Greens parties varies hugely from state to state.

In a closed Facebook group for NSW Greens to confidentially discuss the party a link to our story was posted.

In Cold War style language one Green called for leakers to be identified and punished writing:

Those traitors leaking are attempting to split the party into those believe in our inherently socialist principles and those who see socialism as a political "evil".

During a bruising internal war in 2011-12 over the party's Israel boycott the NSW wing discussed forcing MPs who disagreed with the policy to resign.

To be fair, the NSW Greens are well ahead of the curve on transparency on one other measure.

The party has moved to publish information about all donors pledging more than $1,000 as they are received.

Voters won't find out who gave what to the other parties until well after the election.

Conor Duffy is a reporter with ABC's 7.30 program.