Mr Byrne says the move, to be voted on at this weekend's ACT Labor conference, will democratise the party and give more people a vote on Labor candidates. But, with the push coming from the left faction, opponents fear something is afoot, and say it will open the way for branchstacking. The party is alive with talk about preselection for the federal seats, with suggestions the left is trying to ensure it gets the numbers to control a third federal seat.

Mr Byrne will move a motion scrapping the need for members to attend a minimum number of sub-branch meetings and policy meetings before they can vote in preselection. Instead, anyone who is paid up and a member for one year will be able to vote.

Mr Byrne says that will result in as many as 1500 people voting, instead of 500 now, and extend voting to people who are unable to to attend meetings.

Mr Byrne's left faction has the majority of conference votes and could push the change through, but four sub-branches have passed resolutions opposing the move, and the right faction, which meets on Thursday, is opposed.

Party members said sub-branches were the core of the party and if people no longer needed to attend meetings to be eligible to vote the structure would not survive. Sub-branches also protected against branchstacking because of the need for new members to attend meetings and because the presence of a sudden influx of new members was more obvious.

Chief Minister Andrew Barr, who is in the right, has refused comment, his spokesman saying all enquires about the party and the conference should be directed to Mr Byrne.

Pushed for his viewpoint as leader on such as significant change, the spokesman said, "The chief minister has more to focus on than a rule change in the party."

Right convenor Dave Smith said the faction was opposed at this stage, but open to negotiations.

"There's been no rationale provided for the extent of the changes. At the moment you need three meetings or interactions with the party per year and it's going from three to zero, so we've got some real concerns that it would be a recipe for branchstacking," he said.

He hoped there was "still time for some sensible conversations" on a compromise that "encourages participation in the party rather than this that does the opposite".

"We would be interested in trying to get a better understanding of what's wrong, what are the real drivers for this change, because they certainly haven't been raised across the party before these changes that have come, dare I say, from left field."

Former politician John Hargreaves, also in the right, said he believed the move was "an exercise in branchstacking", with the left "flexing a bit of muscle" to ensure it won the third federal seat.

If the ACT get a third seat as a result of population increases, the factions will scramble to divide the spoils. At the moment, the right (Gai Brodtmann) and unaligned (Andrew Leigh) control one lower house seat each. The left has the Senate seat, in the hands of Katy Gallagher. If there is a third lower-house seat, the left wants one of its candidates in the spot.

It is unclear whom that would be. While Angie Drake, a former local candidate and staffer to deputy chief minister Yvette Berry, is the most commonly mentioned name for the spot, Ms Drake lives in the south, as does Ms Brodtmann. Her candidacy would also offend Labor's affirmative action rules which divide the seats equally between men and women. With two women already in the federal seats, a fourth seat would go to a man - a complication which has Labor figures talking about Ms Brodtmann being replaced by a right-faction man, leaving a left spot open for Ms Drake, which in turn is a scenario that others dismiss as impossible.

Ms Drake said it was not something she had considered.