Leading article: A robust contest will help to define the Liberal Democrats more clearly

Something is lacking in the Liberal Democrat leadership election. Unlike in the recent Tory contest, there is no young charismatic candidate offering unpredictability and promising a radical change in tone. Nick Clegg and David Laws have missed an opportunity. As the example of David Cameron showed last year, either might have won and could have transformed their party's fortunes.

But at least we are still likely to have a robust contest, even if it will not be as definitive for the party as we would have liked. This is far preferable to a "coronation" election, of the sort that was briefly mooted when Sir Menzies Campbell was the only declared candidate at the beginning of the week.

The Liberal Democrats must use this election to conduct a debate on where they stand on key issues. What is their position on public service reform? Are they in favour of higher taxation for the rich? These are crucial questions because we need to know whether this is a party of the centre-left or the liberal right if it is to be taken seriously. One hopes a contest ensures the party will, at last, define itself.

Life will be much tougher for the Liberal Democrats in the era of Gordon Brown and David Cameron. Already they have been squeezed in the opinion polls since the arrival of an engaging new Tory leader. It would be madness to abandon the centre ground, of course. But the Liberal Democrats still need to know which banner they will be fighting under in the next general election, which is one of the reasons Charles Kennedy had to go.

At the beginning of this week Sir Menzies, the acting leader, had it all to lose. He enjoyed the backing of one third of the party's MPs and the support of two former leaders. But Sir Menzies has had a bad week. The low point was Prime Minister's Questions, when he asked a naive question to the great amusement of the chamber. It is an unfortunate phenomenon of modern politics that a single - and relatively minor - mistake can undo years of good work. Perhaps of more concern to his supporters should be his clumsy overtures to the party's left. Sir Menzies no doubt regards this as a tactical measure; the trouble is that he has always been seen as belonging to the right of the party and shifting his ground in this way makes him look desperate.

Mark Oaten, the Liberal Democrat home affairs spokesman, has shown signs of imagination in both his brief and his fledgling leadership campaign. But he is not overburdened with charisma and, so far, does not feel like the answer to the Liberal Democrat dilemma. The same is true of Chris Huhne, the economics spokesman. He was shrewd to see the gap in the field for a candidate of the right and standing for leader will raise his profile but, again, it is very difficult to see him emerging as leader.

So the field appears to be opening up for Simon Hughes. The current Liberal Democrat president would give his party a clear centre-left flavour at a time when the others are huddling together in the centre. On the other hand, the drawback of a Hughes leadership would be that a majority of his Westminster colleagues would be to the right of him. And it would suit the Tories to have a Liberal Democrat leader they could label an outdated "tax and spender".

This weekend it remains hazy as to who will emerge as the new Liberal Democrat leader. But the answer to a different question seems to have been answered by the events of this week. The fact that both the Liberal Democrat and Conservative leaders at the next election will have been directly elected by their respective memberships demands that the same should be true of the next Labour leader. It calls into question any planned coronation for Gordon Brown when Tony Blair steps aside.