There is considerable agreement that the European Union badly needs reform, including constitutional reform, but there is a division between Britain and Brussels about the direction that reform ought to take. It is a question of who should get the power: Parliament or bureaucrats. Most British people want to to see a more liberal Europe, with more democratic values. What they now see is an increasingly bureaucratic Europe, in which power is still moving towards nonelected bodies. The proposed constitutional treaty, which will be renegotiated at the Berlin summit in June, would centralise power even further, taking it from elected national parliaments and giving it to the nonelected bureaucracies. The British thought that they had the safeguard of the guarantee of a referendum; that is now in doubt.

Election manifestos are a sort of contract between the parties and the voters. Since 1945 there has been a doctrine of the election mandate. The party that won an election had a right to carry out the legislation that was specified in its manifesto. Such policies had the weight of democracy behind them.

The terms of the manifesto contract are binding on both sides. Circumstances do change, and governments must be allowed some flexibility in carrying out their programmes. Yet, in principle, governments are not entitled to include promises in their election programmes, and then, if they win the election, just forget about them.

Such changes of policy will always look bad, but they range in importance from allowable flexibility to gross electoral, or even constitutional, deceit. In the end, the voters will decide whether they have been conned.

Last week the Prime Minister let it be known to some European journalists that he was no longer standing by his 2005 commitment to hold a referendum on the European constitution, which has itself been defeated in the Dutch and French referendums. Angela Merkel, the German Chancellor, is now trying to resurrect the constitutional treaty, in a modified form, but with unchanged legal effects. She has circulated the European governments with a memorandum, which includes this rather disingenuous question: “How do you assess the proposal made by some member states to use different terminology without changing the legal substance?” It is clear from this letter thatMs Merkel contemplates rewrapping the constitutional treaty without altering the contents of the parcel.

Tony Blair now argues that Britain would not need to have a referendum, because the revised version would not involve constitutional changes. He cannot possibly know that, at least until negotiations have been completed in Berlin. Plainly, Ms Merkel wants real constitutional changes; for her, the revisions of the Treaty would be cosmetic, designed to avoid the need for referendum in Britain, France and the Netherlands. Once again, Mr Blair is more concerned with spin than substance.

At the 2005 general election, Labour and the Liberal Democrats were both in favour of the Constitutional Treaty, and the Conservatives were against it, but all three parties committed themselves to holding a referendum. This was the specific statement in the Labour manifesto: “It is a good treaty for Britain and for the new Europe. We will put it to the British people in a referendum and campaign wholeheartedly for a ‘Yes’ vote to keep Britain a leading nation in Europe.” That is an unqualified commitment; there is no reference to the possibility of ratifying the constitutional treaty in some amended form, but without a referendum.

The European powers, who are involved in the Berlin renegotiation, need to be aware of the British constitutional problem that Mr Blair has created for himself. He — or his successor — could secure public ratification for a renegotiated treaty, if he carried out Labour’s manifesto commitment to hold a referendum. Such a referendum would, however, probably be lost. His successor could change the 2005 commitment, if he called an early general election and included a manifesto commitment to ratify the new treaty through the parliamentary route. However, such an election, without a referendum, might also be lost. The EU is not popular, nor is the Government.

The third possibility is that Gordon Brown might tear up Labour’s commitment to a referendum and use the current parliamentary majority to ratify the treaty; in that case, there would be no referendum and no election. However, the Tories are opposed to the present treaty, and to any treaty likely to be negotiated. There is no reason why the Conservatives should not maintain their commitment to a referendum. In the event of a Conservative victory at the next general election, they could then hold a referendum, with the new Government advocating a “No” vote. Britain would then be free to withdraw from the operation of the new treaty, which would not be binding in British law. If Labour ratifies without a referendum, the Conservatives will be free to overturn that ratification.

The latest possible date for the next general election is June 2010. The Berlin summit will come three years before that date. June 2010 is, therefore, the earliest date at which the European governments can be sure to know the mind of the British people.

What is the real argument against a referendum? It is simple and compelling. The advocates of a constitutional treaty believe that they would lose a referendum. They think the British voters would vote “No”, and they are not prepared to risk it. So they want — as Mr Blair wants — to ratify the proposed treaty against what they consider to be the will of the British people.

I do not doubt that they are correct in their view. The European Union has developed as an over-centralised, over-bureaucratised structure. In Germany the EU is now responsible for 84 per cent of legislative acts, with parliamentary democracy left with the other 16 per cent. The same, or something like it, is true of Britain. The EU bureaucracy has become a burden for the European nations. The constitutional treaty would only make that worse. The British have been promised a referendum. The electorate should hold Labour to that promise, or make it pay a heavy price in votes.

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