About 62 per cent of members voted for the 50/50 model against 38 per cent for the current model, and when asked to pick between one member one vote and the 50/50 model, the votes were split 49 per cent to 51 per cent.
Greens leader Adam Bandt said he had publicly supported greater membership involvement in the selection of leader, but the threshold for change had not been reached.
“Let’s now keep working together to elect more Greens and put in place a Green New Deal,” Mr Bandt tweeted on Tuesday evening.
Mr Bandt was elected by partyroom members in February following the shock resignation of his fellow Victorian, Senator Di Natale, who will leave parliament in the coming months after his successor is chosen by the state’s members.
The plebiscite campaigns had split a traditional bloc of Greens factions, with past party leaders Bob Brown, Christine Milne and Richard Di Natale campaigning for a 50-50 model, similar to that of the Australian Labor Party, where the vote of elected MPs is weighed against the rank-and-file memberships.
However former NSW senator Lee Rhiannon, her replacement Mehreen Faruqi, former West Australian senator Scott Ludlam and Queensland state MP Michael Berkman and South Australian state upper house member Tammy Franks encouraged members to support the one member, one vote model.
Brisbane City Councillor Jonathan Sri said giving Greens members a direct vote on who leads the party was “an important check and balance” to ensure power did not become too heavily concentrated and centralised.
“Although the result fell just short of the 66 per cent threshold required to change the constitution via plebiscite, the members have shown a clear preference for change,” he said.
Mr Sri said the Greens National Conference should heed members’ voices and enact the necessary changes so the next time the Greens have to choose a new party leader, every single member gets an equal say.
“It’s no longer a question of whether we should shift to a ‘One Member, One Vote’ system, but a question of when that will happen,” he said.
“It would obviously be preferable to change the voting system soon, so that this debate doesn’t drag on into the lead-up to the next federal election.”
Rob Harris is the National Affairs Editor for The Sydney Morning Herald and The Age, based at Parliament House in Canberra