UPDATE (Wednesday 11 June, 21:09): The House of Lords has rejected a referendum proposal by 280 votes to 218.
As expected, Lib Dem peers voted against a referendum, which would have been approved if they had abstained in accordance with Nick Clegg's policy in the Commons.
So will Nick Clegg have the integrity to take responsibility for his party's damaging multiple U-turns, ending up acting completely in contradiction to a popular manifesto promise? Or will he admit he has lost control of his party? It's one or the other, surely ...
Tomorrow there will be a key vote in the House of Lords on the question of whether there should be a referendum on the re-named EU Constitution - now called the Lisbon Treaty.
Due to the different make-up of the House of Lords, with a large number of 'crossbench' peers not linked to any party holding the balance of power, a referendum amendment would very likely be approved if the 76 Liberal Democrat peers obeyed Nick Clegg's policy to abstain on the question.
However, the leader of the Lib Dem peers Lord McNally has already made clear that he and his colleagues will not be abstaining like the party's MPs.
The new instruction is to vote with the government, against a referendum.
The question is - on whose instructions? Either Nick Clegg has performed yet another policy U-turn, and told Lib Dem peers to vote with the government rather than abstain.
Or the peers are doing as they please and just plain ignoring him.
So Clegg must either take responsibility for the fact that his repeated U-turns on the popular referendum promise his party made at the last election are haemorhagging both credibility and popular support. Or admit he has lost control of his party.
Lib Dem voters back referendum
Back in March an ICM poll conducted for the Iwantareferendum campaign found that Liberal Democrat voters supported a referendum on the Lisbon Treaty by more than two to one.
67% said that “Voters should decide in a referendum” while only 30% thought that “MPs should decide in Parliament.”
Shortly afterwards, most Lib Dem MPs having abstained on the issue in the key Commons vote, the party performed terribly in the local elections, failing to capitalise on the flow of voters away from Labour. Particularly in areas where their promise-breaking stance on a treaty referendum was highlighted the most intensely.
A matter of trust
The potency of the treaty referendum at the ballot box has been grossly underestimated by the government and the Liberal Democrats.
Noting that the European Union comes low down the list of voters' concerns, they schemed that they could confront the evident strong public support for a treaty referendum and get away with it.
However, typically of today's political class, they gave scant regard to the 'small' matter of their manifesto promises.
The promise-breaking nature of their actions has caused the referendum issue to transcend into a matter of trust. And the high profile failure to deliver a clear and popular promise made at the last election - almost regardless of the issue itself - is a much bigger electoral liability.
From that point on, nothing a promise-breaking MP says can be believed - a distasteful trait the memory of which also lingers far longer than the details of the act that confirmed it. Hardly a good basis for an MP to request support.
So this issue is not so much about the referendum itself anymore. It has become a matter of trust. And MPs who have appeared to hold trust - much more so than voters' concerns about any single issue - so cheaply are far more likely to pay a heavy price at the ballot box.
In this context, if Lib Dem peers block any chance for the party's MPs to redeem themselves, tomorrow's Lords vote could be the last event standing between the Lib Dems and meltdown at the next general election.
With a high proportion of the party's MPs in marginal seats, the Lords' actions will place over 30 of their parliamentary colleagues and the future leadership prospects of Nick Clegg firmly in the firing line.
The only way back from their predicament is for the party's MPs to be given a new opportunity to support the referendum that they promised at the last election.
So when they vote today, those peers must either vote for a referendum as the party promised at the last election, or at least vote in line with their party leader's policy and abstain.