The future process to deal with same sex marriage reform remains in the balance. The Labor Opposition, opposed in principle to a plebiscite, now holds the key.
Despite majorities in each house of parliament in favour of legislative change, the government still plans to proceed with its plebiscite, first announced as policy by the Abbott government in its dying days. All that remains is to finalise the plebiscite question and to steer it through the parliament. It must now rely on a change of heart by a reluctant Labor.
The government is proceeding despite the cost, warnings about divisiveness from some community leaders and the fact it is not the personal preference of Malcolm Turnbull.
The government stance is not only the policy it took to the recent elections but, more importantly, a delicate compromise between conservatives and liberals, sealed in a deal when Turnbull became prime minister last September. Prominent Liberal campaigners for same sex marriage, including newly elected Tim Wilson, are now enthusiastically backing this stance.
Campaigners for same sex marriage, almost all opposed to a plebiscite because it invites a hurtful campaign, are now split between those who would grudgingly accept one in order to pursue their goal and those willing to wait years if necessary for a parliamentary vote.
As well as fears about the impact of the tone of a plebiscite campaign on the gay community, some advocates are also clearly worried that a plebiscite could be lost despite current majority public support. This is a realistic fear given Australia's referendum record.
Opponents of same sex marriage support a plebiscite as a last resort because it gives them an opportunity to derail parliamentary action by demonstrating majority public opposition. They remain hopeful a silent majority will prove the public opinion polls wrong.
If the plebiscite goes ahead with Labor's support nearly everyone with a stake in the outcome will participate vigorously even if supporters of same sex marriage reform remain disappointed at being put through such a campaign.
"Bill Shorten too will inevitably share some of the blame if post-plebiscite surveys show that the pattern of voting among Labor supporters was not strongly enough in favour of same sex marriage."
It will test the skill and resolve of the major party leaders, both advocates of same sex marriage reform, because the recriminations will be enormous if the plebiscite fails. The leadership of Turnbull, confident that the plebiscite will pass, will become untenable. It would be seen as another campaigning failure and evidence that he is out of touch with majority social attitudes, reinforcing the perceptions of his conservative opponents. Turnbull must campaign from the front for a Yes vote for this reason alone.
Bill Shorten too will inevitably share some of the blame if post-plebiscite surveys show that the pattern of voting among Labor supporters was not strongly enough in favour of same sex marriage, though he will be spared a serious split among his parliamentary colleagues and will be able to explain that he did his best to resist the plebiscite.
Both men will have to balance the time and effort they devote to the plebiscite campaign against the normal duties of parliamentary leaders. This sensitive balance will apply especially to Turnbull with his party critics ever ready to claim he is neglecting his primary 'bread and butter' economic policy duties. On the other hand if the plebiscite bill is defeated in parliament Labor, the Greens and Nick Xenophon will bear responsibility for not taking the opportunity offered even if it is in their view a second-best option. The government is already labelling them as same sex marriage wreckers.
If before too long a parliamentary alternative, such as a free vote, is found to advance the cause of same sex marriage then the rejection of the plebiscite option will come to be applauded as a master stroke. But if years pass by without positive action then there will be some regrets and inevitable recriminations for not grasping the moment of possible success.
The current stalemate may be dignified as a battle of ideas about the most appropriate way of dealing with a matter of deep social importance in a parliamentary democracy. Public involvement through a plebiscite is undoubtedly attractive, but in this instance it is not an appeal to popular sovereignty but a political tactic.
John Warhurst is an Emeritus Professor of Political Science at the Australian National University and a former chair of the Australian Republican Movement.