Much of the discussion arising from Malcolm Turnbull’s emergence as party leader is about his ability to influence Liberal policy without a backlash which could threaten his authority, blur the party’s message, and harm its electoral prospects. That risk has raised questions about the meaning of democracy and the nature of a politician’s duty.

It is seen in the party’s unresolved dilemma over same-sex marriage, supported by Turnbull and other progressives, but on which a ‘conscience vote’ was ruled out in mid-August in a joint party meeting with Nationals; it chose to put the question directly to the public at or after the next election.

The decision is controversial because critics believe it is a waste of public funds – $160 million – when comparable issues of social policy, no less contentious, are routinely settled by elected members. But conservatives had an invidious choice: to vote against reform must highlight tensions and undermine unity, but if they change their views so soon the public will think they have no principles.

Readers will recall the same choice faced party members when Brendan Nelson succeeded John Howard and was prevailed on, notably by Malcolm Fraser and Turnbull, to support the apology. Those who had aligned themselves for a decade with Howard’s intransigence changed their stance virtually overnight – certainly none was prepared to question the new wisdom, just as none had challenged the old. It was, and remains, a demeaning experience for Liberal members and their supporters.

However that may be, the plebiscite is now defended as the ‘most democratic’ way to deal with gay marriage, which is no less an issue of principle. It is not, supporters of the national vote insist, inconsistent with a commitment to representative democracy, but an exception justified by the importance of the family as a bedrock institution in our social and political life.

Underlying this claim, which is disputed by reformers who also see family values as fundamental, is a popular assumption – rarely examined in public life – that when all is said and done the judgment of a majority is the best way to resolve controversial issues of social and political morality.

But it is not hard to see why this view rests on a misunderstanding of democratic theory, and why a majority vote cannot provide a test for what is right or wrong. It is, in essence, a theory of the right to exercise power and says only that the representatives of the majority have a stronger right than those of a minority or any other person or group.

It does not say the majority, with power in its hands, can make whatever laws it likes, or that bad laws are good laws if they get enough votes. Whether a law is wicked or foolish or wise or just is judged by community values, not by counting heads.

Whether a law complies with these values is a matter for argument and parties will typically offer interpretations of what they require, based on their sense of past as well as hypothetical examples which are not in dispute, and which they see as exemplifying or clarifying the meaning and importance of these abstract standards. It is also the kind of argument needed to clarify whether a plebiscite is an exception to, or inconsistent with, the principle of representative government.

We could not distinguish democracy from mob rule …

The above distinction between values and a consensus of opinion on moral issues is fundamental to all social and political argument – without it we could not distinguish democracy from ‘mob rule’ – we could not, for example, condemn an elected government if it chose to outlaw rival parties, pass laws to execute opposition leaders or seize the property of dissidents, as has occurred in Egypt in recent years.

If majority opinion is not a moral value, is there any other reason for a referendum on divisive issues when a vote for law reform does not require constitutional change? If so, no-one has yet articulated it. There is, on the other hand, a good case for upholding the Westminster principle of representative decision-making, including on such major issues of principle as reform of the law to recognise same-sex marriage.

That case rests on the nature of an elected member’s duty which is to act in the best interests of the community and with respect for principles he or she sees him/herself sharing with other citizens. This is different to the duty of electors, who are free to vote their interests and have no duty to educate themselves on policy before they vote. No-one has described this duty of members better than Edmund Burke, widely seen as the father of conservative political philosophy:

‘It is his duty to sacrifice his repose, his pleasures, his satisfactions, to theirs; and above all, ever, and in all cases, to prefer their interest to his own. But his unbiassed opinion, his mature judgment, his enlightened conscience, he ought not to sacrifice to you, to any man, or to any set of men living….Your representative owes you, not his industry only, but his judgment; and he betrays, instead of serving you, if he sacrifices it to your opinion.’

Apart from an early treatise on aesthetics, Burke did not contribute to philosophical debates. He prided himself on being a practical man, not a ‘dabbler in abstractions.’ But he did, it seems, have an intuitive sense that a judgment based on informed conscience is necessarily a conscientious judgment of relevant values, and perhaps the closest anyone can get to an ideal of moral truth on contested social and political issues – that is, issues which lead politicians to appeal to values to justify their views.

This is an important insight, reminding us that the relationship between a judgment of conscience and community values is as much a philosophical issue as a psychological one. However that may be, there is a good case that for Burke acting on conscience was the same as taking a stand on principle. If so, then his eminence as a political philosopher rests as much on his commitment to principle as on his reputation as a champion of conservative politics.

Most politicians will, if pressed, agree with Keating that policy should always have priority over politics, and an underlying assumption – which no one seriously disputes – that policy should rest on arguments of principle. But, because citizens – unlike elected members – are free to vote their interests, the principles in point are put at risk whenever politicians seek to avoid responsibility by an appeal to popular opinion.

Max Atkinson is a former teacher at the University of Tasmania Law School with interests in legal theory and and international law.

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• Max Atkinson in Comments: There is a flaw in the article which is more obvious on re-reading: In my concern to use the plebiscite as an opportunity to discuss the philosophical difference between a moral judgment and the opinion of a group of people, such as a majority, on a moral issue, I never properly addressed the question posed by the title.