The unprecedented number of candidates contesting the current presidential election has focused attention on a peculiar contradiction. On one hand is the widely acknowledged constitutional reality that an Irish President, once elected, can do little to advance a personal policy platform. On the other is the inexorable logic of any election campaign, in which each candidate must set out a distinctive stall in order to win votes from rivals.

Political correctness does not allow us to treat a presidential election as a popularity poll. Nor does it allow the candidates to ask for our support simply because they are nice people. So how are voters meant to choose between candidates, and how are candidates meant to fight elections, given a constitution which guarantees that the winning candidate will have little or no opportunity to honour most of the promises typically made during any election campaign?

Our starting point must be the remarkable level of agreement on the place of the Presidency in modern Ireland. There is a general desire for a head of state who rises above the cut and thrust, and the sometimes sordid realities, of day-to-day party politics.

On the home front, this means formally presiding over the political game, handing out the badges of office to the winners and taking them back from the losers, signing Bills into law and generally filling what would otherwise be an awkward vacancy at the top of the constitutional pyramid.

The other key role for a head of state is to personify the nation. At a practical level, this means meeting other heads of state, receiving ambassadors and going on state visits. At a more emotional level, it means having someone whose persona does in some important way represent how we see Ireland today, and how we want others to see us.

Every European country has a head of state to do these jobs. A surprising number still have hereditary monarchies, for example, Belgium, Denmark, the Netherlands, Norway, Spain and Sweden as well as Britain. Where there is no monarch, there is always a president who acts as head of state. This person is often directly elected by the people, as in Austria, Finland, France, Iceland and Portugal. The alternative is indirect election by the legislature, as in Germany, Greece, Italy and Switzerland.

Additional presidential powers in Ireland take tentative steps beyond this purely formal and symbolic role. These include important and regularly-used powers to refer Bills to the Supreme Court. They also include the power to refuse a dissolution to a Taoiseach who has lost the confidence of the Dail, a power that could be used to huge political effect.

The very knowledge that this presidential power was there, in the hands of someone who might well have used it, was an important feature of the political convulsions of November 1994. There is also the never-used and seldom-discussed power, under Article 27, to refer Bills to the people if so petitioned by a majority of the Seanad and one-third of the Dail.

A move in the European direction would give the President more real political power. There are good arguments for strengthening the position of a person whom we may want to act as a referee in the political game. The Italian president, for example, never previously seen as a particularly powerful actor, played an important role in overseeing the political system during the corruption scandals that struck at the heart of Italian party politics a few years ago.

Additional powers could include much more discretion to refuse a dissolution of the Dail, for example, and much more opportunity to make speeches to the nation on matters of public concern.

However, there seems no great desire in Ireland to expand the political role of the Presidency. The argument against doing this is that giving the President new powers could drag the incumbent into the political mire in a way that would actually undermine the type of Presidency that most people now seem to like.

Side by side with the popular desire to keep the President "above" politics is the wish to have a popular election to decide who gets the job. On the face of things, direct election by the people seems to offer the prospect of a powerful President with a popular mandate to take on the government and/or the legislature. This is one of the arguments used to explain the power of US and French presidents. But 60 years of experience have shown that rigorous and explicit constitutional constraints prevent this in Ireland.

Herein lies the rub. In the past, constitutional hobbling of the President posed no problem in presidential elections, which were rather like local or European elections. While ostensibly about one office, the Presidency, a county council or the European Parliament, they were really another way for voters to pass a midterm judgment on the state of the national political system.

This meant it didn't matter that the President had no real power. Candidates represented the main parties and were automatically different from each other because they had different party labels. Voters were asked to support presidential candidates as part of a wider political game.

An important implication of this was that presidential candidates were people at the end of their political careers. This was because such people, if elected, could plausibly retire from life as partisan politicians to a position above politics: the political system had nothing more to offer them after the job of President was done.

What changed with the Robinson Presidency was the election of someone who was not a conventional partisan politician, someone who was certainly not at the end of her career, indeed someone who went on after holding the Presidency to a very senior position in the international arena. She was a person to be taken seriously in her own right, not as a party politician.

In an era of voracious mass media always craving new angles on anything, Mary Robinson gave a new angle on how to represent Ireland. She became a symbol of a more modern, more self-confident and more prosperous Ireland, and people grew to like the idea of a President who represented the present rather than the past.

In this sense, the most important thing that Mary Robinson changed about the Presidency was the type of person that many want to see as a symbol of the nation. There is no longer much of an appetite for political retirees, however eminent, set apart from each other by no more than party labels.

This represents a very healthy updating of a traditional role, an updating that the British monarchy, for example, has signally failed to achieve. But it does leave one big problem. A presidential election is now about picking a person because of what they have to offer for the future rather than what they have done in the past. How can we hold such an election without having the candidates make us promises about the future that they cannot realistically fulfil?

That is the question to which nobody yet knows the answer. There may indeed be no good answer to it, in which case the new Irish presidency will have to change again, and turn into something quite different from what we can we see today.

Michael Laver is professor of political science at Trinity College Dublin and was a member of the Constitution Review Group. His recent books include Making and Breaking Governments (1996); Private Desires, Political Action (1997); and Playing Politics: the Nightmare Continues (1997)

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