Leading article: Mr Clegg and a question of authority

If there was one party leader who should have come out of the Commons debates on the European Reform Treaty smiling, it was Nick Clegg of the Liberal Democrats. Gordon Brown was saddled with Tony Blair's cynical promise of a referendum, which had been enshrined in the party manifesto. David Cameron leads a generally eurosceptic party that numbers some highly articulate pro-Europeans among its MPs. This week's referendum debate was going to be comfortable for neither leader.

The Liberal Democrats, on the other hand, have been unambiguously in favour of the EU. In their youthful and multilingual new leader, they have a model British European. So for this party to be the one to emerge from the referendum debate most damaged took a special kind of ingenuity – or rather, a special kind of political clumsiness.

Mr Clegg, it is true, had a problem. He inherited from Sir Menzies Campbell one of the more ill-advised compromises of his unhappy time as leader. Instead of embracing or rejecting Tony Blair's proposed referendum on the EU Constitutional Treaty, Sir Menzies had called for a new referendum on EU membership – as he said, to settle things once and for all. This seemed a strange approach when Sir Menzies adopted it. But with an election presumed to be imminent, and the Conservatives under David Cameron looking threatening, it was just possible to discern method in Sir Menzies' madness.

With a snap election no longer on the cards, however, and Sir Menzies' maladroit parliamentary tactics a factor in his demise, there was no reason for Mr Clegg to continue this line. Indeed, there was every reason for him to abandon it. He could have set out as the leader with a demonstrative pro-European stance, rather than sitting disconsolately on the sidelines. By ordering his MPs to abstain, Mr Clegg chose the worst possible option. By remaining in their seats as other MPs went through the lobbies, Liberal Democrats appeared stubborn and negative.

They also looked – a particular trap for the party, this – as though they were unable to make up their minds. For committed Europeans, however, the choice was easy. By this week, the only reason for any MP to endorse a referendum was the expectation that it would produce a No vote.

Mr Clegg should have led his MPs through the lobby after Gordon Brown. Faced with a rebellion, he was left with no choice but to impose the leadership he had failed to exert before. Had he shown the courage of his convictions earlier, he might still have had to replenish his front bench, but at least the principle at stake would have been clear. As it is, he must work to re-establish his authority.