The European Union has been plunged into uncharted constitutional waters following a parliamentary committee's rejection of Italy's nominee for European commissioner, Rocco Buttiglione.
The Civil Liberties Committee voted against his appointment as justice, freedom and security commissioner by a majority of 27 to 26, and also opposed his being moved to a different portfolio by 28 to 25.
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MEPs were angered by his support for creating transit camps in Africa for asylum-seekers, by his views on the place of women in the family, and especially by his stance on homosexuality.
Mr Buttiglione told his parliamentary hearing that homosexuality was a "sin", claiming that this would have no effect on his political activities so long as he did not think homosexuality was a crime. He conceded, however, that he would oppose any Commission proposal which ran foul of his moral principles.
The President of the European Parliament, Josep Borrell, added his voice to the opposition to Mr Buttiglione's candidature, saying: "It does not seem to me that in this day and age we can have people in charge of justice - especially justice - who think like that".
The biggest grouping in parliament, the centre-right European People's Party, has expressed "full confidence" in Mr Buttiglione, so there is no certainty that the views of one committee will influence the confirmation vote, due to be held at a full session of parliament on 27 October.
In any case, MEPs cannot pick and choose: they must vote for or against the 25-member Commission team as a whole.
But there is no precedent for what happens next. Over the coming days, each political group in the European Parliament will meet to discuss the candidates and - as one MEP put it - "to let off steam".
The presidents of the political groups will then hold talks with the parliament's president, Mr Borrell, and, on 21 October, with the President of the Commission, Jose Manuel Durao Barroso.
It is at that meeting, just days before the final vote, that some sort of compromise may have to be struck. MEPs will expect some movement from Mr Barroso - especially as Mr Buttiglione is not the only commission candidate to have met with disapproval.
MEPs have also criticised the performance of the Dutch commissioner-designate, Neelie Kroes, who is nominated for the competition portfolio, of the Danish agriculture commissioner Mariann Fischer-Boel, and of the proposed taxation commissioner, Ingrida Udre from Latvia.
According to Richard Corbett, an MEP and expert on EU constitutional matters, Mr Barroso has several options.
"He might say: This is a key member of my team who's failed to pass the initial exam. If I keep him it will be a problem for five years. I'd rather solve it now either by asking Italy to nominate a new commissioner or by reshuffling portfolios or making some other adjustment."
The chances of persuading the Italian Prime Minister, Silvio Berlusconi, to nominate a new commissioner are slim, entailing as it would considerable loss of face.
Reshuffling the entire college of commissioners would also be problematic, and might require several other commissioners to "re-sit their exams" by facing fresh hearings, on a different subject, before parliamentary committees.
Other "adjustments" are possible, though.
One precedent is the case of Padraig Flynn, the Irish representative in the commission led by Jacques Santer in 1994-1999.
Members of parliament objected strongly to his views on women, and as a result that policy area was removed from his social affairs portfolio.
Something similar could happen in the case of Mr Buttiglione.
These hearings have turned into something rather more exacting than many of the nominees may have expected. Members of the European Parliament are keen to show they are no push-over, and many will be tempted to veto the entire Commission if they are not satisfied with Mr Barroso's response to their concerns.
As one MEP put it, the ball is now in his court.