He may be looking ashen-faced with tiredness; his voice, what's left of it, croaking like a sick frog; but the leader of the Liberal group in the European Parliament, Pat Cox, has a wry grin that says it all.

This was his week.

The quiet-spoken, sometimes painfully serious, independent MEP from Munster emerged from the serried ranks of the European Parliament's chorus line to take centre stage with a coup de theatre that left his rival parliamentary leaders floundering.

Cox may have lost the vote on his motion demanding the resignation of Commissioners Edith Cresson and Manuel Marin, and he may have found himself on the losing side of the no-confidence motion against the Commission.

But history is likely to record that a profound shift in the balance of power to the parliament started this week largely because he was willing to seize a political opportunity that others wanted to shy away from.

Cox's recognition factor has soared. His key speech was interrupted four times with what the official record calls loud applause. In the press room reporters were asking, like Butch Cassidy (or was it the Kid?): "Who is that guy?" In the corridors the view was that he had played a blinder.

The crisis had its origins in the refusal in December of the MEPs to grant a discharge on the 1996 accounts in response to a series of allegations of fraud and mismanagement which the Commission had failed to tackle.

When the Commission President, Jacques Santer, escalated matters by making the issue one of confidence in the Commission, the Socialists rowed in with a motion to express precisely that (or, to be exact, a motion of no-confidence that they would vote against).

In doing so both were playing a dangerous game. The treaty requires a two-thirds vote to sack the Commission, and here were both Commission and Socialists lowering the bar to 50 per cent. To make matters worse Santer issued his threat ahead of the vote, antagonising many MEPs who did not like being bullied.

And there it stood over Christmas as we waited for this week's vote.

Cox understood that the parliament did not actually want to sack the full Commission or even some of its members, but began to see an opportunity in the crisis to advance the long-cherished ambition of the parliament to get the right to sack individual commissioners instead of all-or-nothing.

Ahead of the posse, he put down a motion last week calling on Cresson and Marin to resign.

"Last month," he told fellow MEPs on Monday, "the Commission empowered itself to demand of this House a vote of confidence through the censure route. The Commission has no legal right to do that. But politically it made the choice. This month we can borrow from the Commission's precedent. Let parliament empower itself to call on individual commissioners to consider their position even if no formal legal base exists."

Touche!

To the fury of Socialists, who accused him of irresponsibly usurping powers that the parliament did not have, Cox turned the tables on them to expose the nonsensical nature of parliamentary supervision of an executive based only on what has been called the nuclear option. And it was Cox who was able to argue that the collegiality of the Commission was no bar to individual responsibility.

"In all our democratic systems the undertaking of personal responsibility by ministers for various shortcomings or conflicts of interest, and occasionally their resignation, is seen as a strength not a weakness of the system, " he said.

Indeed it was precisely this reality and a desire to curb the influence of parliament that led successive drafters of treaty changes to deny MEPs such rights.

Cox, a united group behind him, was able then to hold the line consistently throughout the week, while all around others scrambled for compromises that would get them off hooks of their own making.

Meanwhile, the two main parties, the European People's Party and the Socialists, split helplessly along national lines.

Yet by placing the issue of individual accountability centre stage, Cox knew that, even if the Commission was not sacked, a real prize could come out of the week's events. No candidate for commissionership will be allowed to come before the parliament's hearings this autumn without facing the question of where they stood on the issue. Few imagine that if they want the backing of MEPs they will be able to do anything other than support the principle.

Using the limited powers it was given, one of parliament's more imaginative operators succeeded in winning significantly new ground and at the same time stamping his own mark on the assembly.

The 46-year-old Cork man started his career in academic life working for the Institute of Public Administration and then the National Institute for Higher Education in Limerick as an economics lecturer. He joined RTE to work as a reporter and presenter before becoming the secretary-general of the Progressive Democrats after their foundation in 1986.

Elected as an MEP in 1989, he has served in the parliament since then, apart from a spell in the Dail from November 1992 to July 1994.

Having been closely associated with the leadership of the PDs as a negotiator in the formation of two governments, Cox resigned from the party in 1994 after Mary Harney beat him in the leadership contest to succeed Des O'Malley.

In the same year he was elected to the deputy leadership of the parliamentary group of the ELDR under a talented Dutch leader, Guy de Vries, a young politician whose measured, quiet contributions, consistency and clarity had won him wide cross-party respect.

It is a style that has fitted Cox like a glove. The Liberals, like all other parliamentary groups, play the game to maximum party advantage, but have often done so with a subtlety others find hard to match.

The party, the third-largest group in the parliament, has 42 members from 12 of the memberstates. Only Germany, Greece and Portugal are not represented. A centrist party, whose political roots go back to the European revolutions of 1848, it encompasses both left and right currents but is broadly orthodox on economic management issues and has a strong tradition of promoting human rights.

When de Vries went back to Holland last summer to join the Dutch cabinet, Cox was elected leader unopposed, a post that he will hold until the aftermath of the elections in June. After that the arithmetic in the group may be different, but there can be little doubt his performance this week will help his cause.

A gruelling schedule of travel leaves him, he hopes, Sunday free for his wife and six children in their home in Shanakiel.

A cushy number it ain't.