Dr James Hampshire

There's little doubt that British voters are sceptical about immigration in general, and EU free movement in particular. According to the British Social Attitudes survey, over three quarters of the British public think immigration should be reduced, and over half think the right of EU citizens to live and work in Britain should be ended.

Combine these numbers with the fact that EU citizens account for roughly half of those migrating to the UK, and it is unsurprising that the Leave campaign have put immigration at the centre of their argument for Brexit. Leave the EU, so the argument goes, and Britain will regain control of its borders and with that the ability to control immigration.

It sounds plausible, but is it true? There are good reasons to doubt that it is.

First, it is highly unlikely that the EU would grant Britain access to the single market without free movement. So if Britain wants to join Norway and Switzerland as members of the EEA, it will have to continue to accept the right of EU citizens to live and work here.

However, let's assume that a post-Brexit government did bring an end to free movement – almost certainly by leaving the single market. What then?

Everyone agrees that it would take a long time for Britain to negotiate a new arrangement with the EU. As discussions unfolded and the prospect of controls loomed, any European who had been thinking about moving to Britain would face an enormous incentive to do so before the door closed.

Something very similar has happened before, when rumours about impending immigration legislation in the 1960s led to a spike in immigration from the Commonwealth in an attempt to 'beat the ban'. Thus the short to medium-term effect of Brexit could be an increase in immigration. As the Leave campaign could reasonably retort, however, this would be a one-off effect. What of the longer-term prognosis?

Outside of the single market it's true that the government would acquire a new legal authority to control EU citizens in the same way as it currently controls non-EU immigrants. But legal authority does not seamlessly translate into government capacity, let alone migration reality.

It's worth observing that the current government has not been very successful at reducing non-EU immigration, despite having the legal authority to do so. This is essentially because although the UK government faces loud political demands to restrict immigrants (and for this reason remains committed to an absurd net migration target) it faces equally powerful, but often quieter, demands to admit them.

Important sectors of the British economy from the City of London to the agricultural, tourism, and healthcare sectors lobby hard on immigration policy. This explains why the Coalition government had to row back on some of its proposed restrictions on work migration, like exempting intra-corporate transferees and highly paid workers from its immigration cap.

Add to this the importance of the international student market for UK universities, plus the fact that attempts to exclude immigrants who aren't backed by powerful lobbies are often constrained by human rights obligations, and it begins to look less clear that Brexit would mean fewer immigrants. And that's not to mention the possibility of new forms of irregular migration from Europe. If post-Brexit immigration policy was tightened while demand for migrant labour persisted, especially at the low-skill end of the economy, Britain would likely experience a new flow of irregular migrants to work in the shadow economy.

Governments have limited capacities to exclude, identify and remove immigrants, and when limited legal entry routes come up against labour market demand on the one hand, and supply of migrant workers on the other, the result is usually irregular migration. Would replacing EU free movers with European irregular migrants represent an improvement? Irregular migrants are more readily exploited, which makes it easier for unscrupulous employers to undercut local wages, and they do not contribute to income tax receipts. 

Thus there is a huge gap between the simplistic claims of the Leave campaign, and the complex reality of governing the world's fifth largest economy, further inconvenienced by the rule of law. In the event of Brexit, the government would come under tremendous pressure from employers and businesses to either admit those (now controllable) European nurses, lawyers, and students as immigrants, or else replace them with people from elsewhere.

Politically, therefore, the immigration issue would not go away, but rather evolve in ways which might lead the government to liberalise immigration policy in the face of employer pressure while simultaneously incentivising new forms of irregular migration by those it excludes. In short, it’s far from clear that leaving the EU really would mean lower immigration.

Dr James Hampshire is a Senior Lecturer in Politics at the University of Sussex

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