Political Commentary : Just suppose we wanted to leave, could we find the door?

A recently retired Foreign Office knight told me the other day that we could not leave the European Community even if we wanted to. It would, he said, be illegal. His view, I confess, surprised me. The European Communities Act 1972, which still governs our membership of the Community - and clearly lays down the supremacy of European law over the home-grown variety - can, after all, be repealed by Parliament, as can any statute. There are no fundamental laws in the United Kingdom, even if a few adventurous judges have suggested lately that there are circumstances where the courts might refuse to give effect to an objectionable Act. Lord Irvine, Mr Tony Blair's mentor and prospective Lord Chancellor, has duly rebuked these heretical spirits for insubordination.

Certainly Parliament often does all kinds of strange things. In 1965 it legislated retrospectively to nullify a Lords judicial decision in favour of the Burmah Oil Company. A year later it deprived, in a couple of days, the Kenyan Asians of all their rights as UK passport holders. In 1991 it created a retrospective criminal offence with the War Crimes Act. Moreover, it used the Parliament Act 1911 to over-ride the Lords' objections and force the measure through. This use of the Parliament Act, though legal, was certainly unconstitutional, for the Bill was neither a major measure of policy nor one which had previously been submitted to the voters in an election.

In view of these and other pieces of skulduggery by the legislature, the repeal of the European Communities Act 1972 should be straightforward. Indeed, at the time the Heath government made much of its repealability. Parliament, it was said, was not giving away its sovereignty as the supreme law-making authority in the UK. For that authority could be reclaimed at any time from the European institutions through the repeal of the Act and our consequential withdrawal from the Common Market, as it was then called.

Sir Edward Heath and his colleagues were not always as frank as they might have been with the voters in those days, whether about their own intentions or the likely development of the Community. But at least they were honest and realistic enough to know that, if we repealed the 1972 Act, we should be saying good-bye. This is more than can be said of Mr Iain Duncan Smith and his chums (about 70 of them) on the Conservative benches today. They think - or say they think - that the 1972 Act can be amended to restore the supremacy of Parliament in our courts and that simultaneously our membership of the Community can remain unaffected.

The Daily Mail and the other Tory tabloids appear, as far as one can tell, to believe the same impossible thing. It would be better all round if politicians or newspapers that wanted us to leave the Community said so straightforwardly instead of demanding the restoration of parliamentary sovereignty. It is not so much that this restoration is not on offer, though it is not, as that it is inconsistent with the Rome Treaty 1957 to which the 1972 Act gives effect in the UK.

The Heath argument struck me as odd at the time. It admitted the very charge which it was purporting to knock down: that Parliament was losing its sovereignty. The counter-argument adopted was that Parliament could take it back at any time. Sir Edward and his allies then went on to say that this was all theoretical legal mumbo-jumbo anyway, of no interest to practical persons such as themselves.

They proceeded to perpetrate a confusion between sovereignty in the sense of the supreme law-making authority within a state and sovereignty in the sense of a state's power to conduct its external relations as it wishes. This muddle is perpetuated by Europhiles to this day. Lord Howe, who is a clever man, at any rate in this limited field, is particularly fond of deploying it, knowing perfectly well what he is doing. Our freedom, the argument runs, is so circumscribed already - by our membership of Nato, of Gatt and of various other acronyms - that our membership of yet another organisation makes no odds. It may even, in a curious way, enhance our sovereignty to the extent that we acquire a greater capacity to influence international events.

This argument was particularly popular in Foreign Office circles during the 1960s, when the department was fighting (and, ultimately, conquering) a sceptical Treasury over the benefits of our membership of the Common Market. So it was not perhaps surprising that my Foreign Office friend, himself a product of those years, took the view he did about the illegality of our withdrawal from the Community. And yet in 1975 we held a referendum on this very question. The voters decided by a large majority that we should stay in. The question of illegality was not raised at all by the supporters of this course, such as Lord Jenkins and Sir Edward.

What has happened since? Well, we have had the Single European Act 1986, which Lady Thatcher whipped through the Commons in a week, and the Maastricht Treaty 1992, from which Mr John Major secured his opt-outs on the single currency and the social chapter. It may be that these measures create enforcable international obligations which were not present at the time of the referendum. I do not know.

What I do know is that leaving the Community is not the course that dare not speak its name which it was even two years ago. But it is canvassed only inside the Conservative Party. Mr Blair's greatest achievement has been to keep Labour ostensibly united on Europe. His attitude to Mr Major's policy of non-cooperation - roughly, that he supports it, but only if it works - seems to me entirely sensible.

In a year's, or even a shorter time, the Europeans clearly believe, they will be dealing with a new and friendlier British Prime Minister. Just as remarkable as the Tories' about-turn since the 1970s has been that of the People's Party since 1983. The change occurred with Mr Jacques Delors's rather dull speech to the TUC in 1988, at the high tide of brutish Thatcherism. Mr Delors offered a convenient refuge to the brothers from the branches. As Charles Wesley put it in his greatest hymn:

Cover my defenceless head

With the shadow of Thy wing.

If Mr Blair has the interests of his government at heart, he will embrace a single currency even before the preliminary introductions have been concluded. The reason is a simple historical one. Every single Labour government since 1929 has had its plans impeded or destroyed by a financial crisis which has occurred two years after it has attained office. With sterling an international currency, even though in a smaller way of business these days, there is every likelihood that Mr Blair's government will meet the same fate. No preventative measures have been suggested by Mr Gordon Brown or anyone else. But whether we join a single currency or not, a Labour government will not take us out of Europe. I should still like to know whether we could leave legally if we wanted to.