Illustration by Ian Sharpe.

Illustration by Ian Sharpe.

Malcolm Turnbull has made a significant contribution to the same-sex marriage debate in his Michael Kirby lecture, which was reproduced in The Canberra Times (''Family first: gay or not'', Forum, July 7, p7). The lecture was not mainly about politics, but when he turns to the politics he commits himself to vote for same-sex marriage, subject to the wording of the bill, if the Liberal Party has a free vote. But he points out that his party has resolved not to have a conscience vote and that the its policy is to oppose gay marriage.

In pointing to these limits on his freedom, Turnbull raises aspects of democratic process that deserve further examination. Democracy in practice is not as simple as it seems. Its operations include rules and procedures involving elections, party policy, voting, bicameralism and so on.

The first aspect in this case is the question of party policy, because that comes first chronologically, and the second is the question of whether the Liberal Party should allow a conscience or free vote.

The position of the parliamentary Liberal Party, as enunciated by Opposition Leader Tony Abbott, is not just that opposition to gay marriage is party policy but that the party specifically entered the last federal election having given that commitment to pressure groups and voters. There is a difference.

This is not just splitting hairs. Election commitments are regarded more seriously than a matter that happens to be party policy but is not specifically introduced into a campaign and included in a party policy speech. Both Labor and the Liberals gave specific commitments to a lobby group, the Australian Christian Lobby, that they would not introduce a gay marriage bill and that they would not support such a bill if it was introduced by someone else. The lobby specifically set out to obtain that election commitment at its pre-election forum with the party leaders, Abbott and Labor's Kevin Rudd in June 2010. They each gave it. When Julia Gillard replaced Rudd, the same question was specifically put to her in a later conversation with the lobby's managing director, Jim Wallace, and she repeated Rudd's anti-gay marriage commitment.

Labor has since introduced a pro-same-sex marriage party policy combined with a conscience vote. Gillard will use her own conscience vote to vote against gay marriage, but the lobby still regards this compromise as having broken Labor's 2010 election commitment.

The lobby extracted these promises from Gillard and Abbott not just because of their personal views , but because the lobby was seen as having political muscle. Following on from Rudd's earlier religion and politics initiative, Labor in particular was keen in 2010, as it had been in 2007, to appeal to the segment of Christian voters represented by the lobby. That is how this game of pressure group-political party relationships is played. Lobby groups get a hearing when they seem to be powerful and their power allows them to obtain agreement from parties and candidates.

Turnbull repeats the gloss on the idea of a conscience vote in the Liberal Party that Abbott uses in his public statements. They argue an unconvincing position by trying to have it both ways. They argue the Liberals are different to Labor because ''unlike the Labor Party our members do not get expelled if they cross the floor. So in that sense every vote is a conscience vote.'' Turnbull does go on to point out, somewhat contradictorily, that crossing the floor is not an option for members of the shadow ministry because of the discipline of solidarity. If they did, they would need to resign from the shadow ministry, an enormous step, and Turnbull does not plan to do that.

Crossing the floor and conscience votes are in fact very different. Those who cross the floor are abandoning party discipline on a matter of principle. Those who take advantage of a conscience vote are doing so with the blessing of their party. While Liberals are not expelled for crossing the floor, some who do so are not forgiven. It is certainly not encouraged. West Australian Liberal Mal Washer, when he was considering supporting Independent MP Rob Oakeshott's compromise asylum-seeker processing bill, was put under enormous pressure by colleagues and he eventually agreed not to cross the floor unless his vote was crucial, which it wasn't in the end. His conscience was certainly not respected as it would have been in a conscience-vote situation.

Turnbull is probably right, however, in saying the parliamentary numbers are not there for gay marriage at the moment (though he reckons they are for civil unions). If that is the case, attention should soon turn to what position the parties will take to the 2013 election.

Sooner or later, when the Australian Christian Lobby or another pressure group like Marriage Equality comes calling, the parties will need a position for 2013. Presumably, Labor will now say it has a party policy supporting gay marriage but allowing a conscience vote.

The Liberals will have a fresh opportunity to reconsider the conscience-vote issue, without the defence that it would be contrary to its 2010 election policy and commitments. Presumably, conscience-vote advocates like Turnbull will be pressing their party for a conscience vote.

What this means for the same-sex marriage debate is that the next federal Parliament may provide a fresh start with some different democratic processes at work. Even if defeated on this occasion, the issue will continue to be debated.

John Warhurst is an emeritus professor of political science at the Australian National University.

john.warhurst@anu.edu.au