There is nothing unusual about branch members discussing the demise of a Liberal premier, a topic that dominated grassroots ALP meetings across the state at the time.

What is unusual about Mount Keira's debate is that it happened eight days before Mr O'Farrell quit on April 15.

The fictitious O'Farrell dialogue is just one of the "manifest and repeated inconsistencies" in the attendance books and minutes of the Mount Keira branch, discovered by Labor's Independent Appeals Tribunal set up as part of Kevin Rudd's intervention into the NSW ALP last year.

The Mount Keira branch was this week declared "defunct" because doctored minutes and dodgy attendance books over months mean there hasn't been an official meeting of the branch since last year. Minutes repeatedly record members talking who were not there, according to signatures in the attendance book.

But Sussex Street party bosses are set to allow members of the tainted branch to participate in a preselection vote on Saturday that is likely to re-endorse Wollongong MP Noreen Hay, a former longtime ally of disgraced powerbrokers Eddie Obeid and Joe Tripodi, as the Labor candidate for the 2015 state election.

But as they push ahead with the preselection ballot they face calls for a "wholesale review" of the Labor membership in the Illawarra and guarantees that Saturday's preselection will be a clean process.

The matter could be referred to the federal ALP after reports that Sussex Street is "pulling out all stops" to protect Ms Hay, the Right's convenor of the state caucus, from challenger Paul Scully, a Wollongong academic.

Last week Fairfax Media revealed evidence of branch stacking by forces aligned to Ms Hay, including the relocation of three Labor members into the house of Wollongong branch secretary Judita Matic, apparently to boost Ms Hay's numbers. They have since been struck off the voting list.

Federal Labor MP for the Illawarra-based seat of Throsby, Stephen Jones, said: "I'm astounded by what you've told me and if it's true it needs thorough investigation."

Cunningham MP Sharon Bird, whose electorate overlays the state seat Wollongong, said as a preselector on Saturday she could not comment directly on the ballot. "But obviously a legitimate voting list and fair process should be a priority for all rank-and-file ballots," she said.

The Mount Keira branch is dominated by former Wollongong mayor and high-profile property developer George Harrison and is a key rock of support for Ms Hay.

Mr Harrison has been contacted for comment.

In a letter to ALP general-secretary Jamie Clements obtained by Fairfax Media, Mr Scully described the findings of the appeals tribunal as "extraordinary" and has asked that Mount Keira branch members be given a "challenge vote", whereby they don't count until an upcoming investigation by the party's Review Tribunal.

"In all the years I have administered ballots on behalf of the NSW branch I cannot recall a similar finding during the course of a public office selection ballot," he wrote.

"The comprehensive denouncement of the record keeping of the Mt Keira branch by the IAT [Independent Appeals Tribunal] naturally raises questions over the eligibility of the members of that branch, who may have relied upon attendance at meetings which may later be found by the Review Tribunal or party officers as suffering from similar inconsistencies in the branch records."

Mr Scully has named six individuals who he believes should be given a challenge vote and named five others on the voting list from the Mt Keira and Wollongong branches who live as far away as Queensland and Queanbeyan.

Mr Clements told Fairfax Media that the six members named by Mr Scully would be given a challenge vote and only be counted if the result is close.

But he denied there is any need for a wider audit of the ALP membership in the Illawarra, saying the Mt Keira branch was an isolated example.

"I'm awaiting the advice from the IAT and we will take action against the Mt Keira branch if there are any irregularities," he said.

Former Wollongong MP Col Markham, who lost in a preselection battle with Ms Hay before the 2003 election, said Sussex Street should step in before Saturday.   

He said: "If they have been found rorting the books and engaging in illegal practices then they should be removed from the voting list, simple as that."

Mr Markham said the Warrawong Branch was disenfranchised 12 years ago amid similar allegations of impropriety.