Will the United Kingdom still be a member of the European Union in 2020? YouGov President, Peter Kellner, examines three scenarios.

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1. The Conservatives win the 2015 election and David Cameron is able to redeem his promise to renegotiate Britain’s membership terms and hold a referendum in 2017.

If current public hostility to the EU remains, it might look as if withdrawal is likely. Most of the time, the voters who want to leave the EU comfortably outnumber those who want to stay in. YouGov's latest poll, conducted on April 21-22, puts the margin at 43-35%. This eight point gap is actually lower than normal: in recent years the margin has normally been 15-20 points. And the bad news for those who want the UK to remain in the EU is that the gap currently seems to have been widening again, even before Nigel Lawson declared his support for withdrawal.

Now for the better news. First, whenever Cameron has made the EU a high-profile issue – such as after the December 2011 EU Council meeting when he was in a minority of one on the Eurozone controversy; or when he made his major speech on EU policy earlier this year – the gap tends to close. In one poll in mid-January YouGov found more people wishing to stay in the EU than leave it.

Second, YouGov has started asking a second question:

Imagine the British government under David Cameron renegotiated our relationship with Europe and said that Britain's interests were now protected, and David Cameron recommended that Britain remain a member of the European Union on the new terms. How would you then vote in a referendum on the issue?

Every time we have asked this question we have found that those saying “stay in” clearly outnumber those who say “get out”. Our most recent poll finds a three-to-two majority for remaining in the EU. The big switch occurs among Tory voters. At present they favour withdrawal; but, given a clear lead from the top of their party, most say they would vote to remain in the club.

I would expect this to happen in a real referendum. Cameron certainly wants to keep the UK in the EU. As Lawson says, his “renegotiation” may yield very little in the form of transferring powers back from Brussels to Westminster; however, he will claim to have protected Britain’s vital interests.

(This is precisely what happened in 1975, when Labour’s Harold Wilson also undertook a “renegotiation” with the Common Market, as it then was, ahead of a referendum. He returned to London claiming a triumph. I was a young journalist on the Sunday Times and obtained an internal Labour Party document showing that Wilson had gained virtually nothing. It was the paper’s lead story one week and caused a brief fuss among those obsessed with politics. But it passed the wider public by and did nothing to impede a two-to-one referendum vote for staying in the Common Market.)

So: in a Conservative-inspired referendum in 2017, the leaders of all three main parties would advocate a vote for remaining in the EU. And they, and much of the business community, would issue dire warnings of how bleak life would be on the outside; only a minority will share Lawson’s view that prosperity would be greater if we withdrew. The unspoken “mood” question would shift from today’s “Do you like the EU?” (majority answer: no), to “Is it better for British jobs and prosperity for the UK to remain in the club than risk the hazards of life on the outside?” (probable majority answer in 2017, as it was in 1975: yes). As in so many referendums round the world, when there is no settled national consensus, the status quo will prevail.

2. Labour wins the 2015 election and Ed Miliband sticks to his current position of opposing a referendum

Here the consequences are simple. Britain would remain in the EU, at least until after the 2020 general election.

Miliband might well make a different referendum pledge: to call a vote if there is any proposal to transfer more powers from national parliaments to the EU. I would expect the status quo to prevail once again. Indeed, I find it hard to imagine any major EU treaty revisions for some years to come, because some country somewhere is likely to hold a referendum, and the experience of the French and Dutch referendums in 2005 on the proposed EU constitution shows that giving Brussels more power is unpopular even in pro-EU countries.

3. Labour wins the 2015 general election with Ed Miliband having changed his stance and promising a referendum on British membership of the EU.

This is much harder to call. The one thing we can confidently predict is that an outright Labour victory would lead to Cameron’s resignation, or ejection, as Conservative Party leader. There is a strong likelihood that his successor would be strongly Eurosceptic.

In these circumstances, a referendum in 2017 would encounter two hazards for supporters of EU membership: first, that the Labour government would be suffering mid-terms blues (for example because it has to take some tough spending decisions or raise taxes in order to tackle continuing economic problems); second that the main opposition party might well be advocating a vote for withdrawal.

The referendum would then be a contest between two propositions: “keep Britain in because life would be tougher on the outside”, versus “say boo to both Miliband and Brussels and vote for Britain to get out”. At this stage, I can’t be sure which argument would be more persuasive; but the possibility of the UK voting to leave the EU would be very real.

One other option – let’s call it 3a – is that Labour promises a very early referendum, say in September 2015. The precedent would be the Scottish devolution referendum in September 1997, four months after Tony Blair became Prime minister. The enabling legislation was passed within weeks of the election and the referendum held straight after the summer holidays.

I would expect that to yield a vote to stay in the EU. A Miliband-led Labour government would probably still be enjoying a honeymoon with the public. Voters would be unlikely to want to punish it so early. And the Tories would be divided on the issue – either they will not yet have a new leader, or the dust will not have settled following the contest to choose one.

All in all, if the parties stick to their current plans, then I see little chance of Britain leaving the EU – unless, of course some existential crisis causes the Union to disintegrate for reasons that have little to do with domestic British politics. BUT – if Ed Miliband decides to match David Cameron’s promise of a mid-term referendum in 2017, then a striking paradox emerges. In those circumstances, anyone whose over-riding passion is for Britain to stay in the EU should vote Conservative – while anyone desperate to maximise the chances of quitting the club should vote Labour.

Click here to view the YouGov/Sunday Times poll - January 2013

Click here to view our Europe referendum tracker



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