This afternoon Lord Livermore made an unusual appeal to the second chamber, urging peers to stand up to the widespread hostility to immigration. This is an edited version of the speech he gave.

By Spencer Livermore

In the UK, as elsewhere, politics has taken a nativist turn, and the debate about immigration has become a conversation only about how far and how fast it should be controlled.

There is almost no discussion about its benefits, nor about the nature and the extent of our economy’s need for it to continue.

As a result, we have a political debate in this country that is failing to serve the interests of the public. Although there is continuing strong support among voters for reducing immigration, there is little or no consideration of the consequences of doing so: for national prosperity, individual living standards, or specific sectors of the economy.

Certainly, the debate about immigration during the EU referendum campaign strained the boundaries of acceptable public discourse.

Nevertheless, the government decided it was central to the referendum's outcome, and chose to make a red line for the negotiations not growth, jobs and living standards, but reducing immigration, regardless of the economic cost.

This perspective – that the economic wellbeing of the nation matters less than the politics of control – has driven the prime minister to pursue the hardest interpretation of Brexit.

Her argument is not that this will make Britain more prosperous, but that controlling immigration is so important it's worth pulling Britain out of the single market and customs union to achieve.

So this report from the Economic Affairs Committee, of which I’m a member, feels timely, both to scrutinise the government's intentions in the EU withdrawal bill, and as we await the much delayed immigration white paper.

It's right that we should ask whether EU migration has had the negative labour market consequences often claimed by its detractors. And it’s right that we should examine the impact reducing immigration would have, in particular whether it would achieve the benefits those who support Brexit claim.

As we do so, it’s vital we proceed on the basis of facts, and I wholeheartedly endorse the comments of the justice minister Dr Phillip Lee when he said: "The next phase of Brexit has to be all about the evidence. There would be a serious question over whether a government could legitimately lead a country along a path that the evidence and rational consideration indicate would be damaging." He went on to say: "It's time for evidence, not dogma, to show the way. We must act for our country's best interests, not ideology and populism, or history will judge us harshly".

So it’s fitting that our report begins by voicing concern about the absence of facts, specifically, the poor quality of the available migration data. We were astonished to hear witnesses repeatedly tell us how little accurate data is collected, how haphazardly it’s done, and how great is the margin of error.

As our Report says: "The data fails to provide an accurate number of migrants entering or leaving the country. It is based on flawed sample surveys, wholly inadequate for policy making or measuring the success or otherwise of the policies adopted".

Whatever your view about the levels of immigration, surely the government must have reliable statistics before it formulates its new policy, otherwise it will be making crucial decisions of vital importance completely in the dark.

What evidence, then, did we find to support the claim that EU migration has a negative impact on the UK labour market? I have always found it odd that anti-immigrant tabloid propaganda accuses EU nationals simultaneously of coming here to sit about on benefits and at the same time of taking all of our jobs. Presumably it would need to be one or the other? The more likely explanation, of course, is that it's neither.

There was little evidence presented to us that foreign workers take jobs that British workers wanted. Many witnesses told us of an unwillingness amongst British workers to carry out particular types of work. We learnt that only one in 50 applicants for vacancies at Pret a Manger for example are British, and the Agricultural and Horticultural Development Board told us that attempts to fill vacancies with UK workers have proved difficult in the past.

Neither does is seem that domestic workers have been priced out of the labour market. Professor Jonathan Portes from King’s College said that "the emerging consensus is that recent immigration has had little or no impact overall", while Stephen Clarke from the Resolution Foundation told us that it would be wrong to say any negative effect had been large.

The evidence is scarce because – although it’s one of the great unsayable truths of British politics – the fact is that immigration is good for our economy.

The benefits are clear: it increases growth, provides more tax revenue, and helps pay for an ageing society. By raising aggregate demand, it creates new job opportunities; it brings skills into our economy, and makes us more competitive.

Indeed, there is substantial evidence that reducing immigration would damage our economy, and – by lowering tax receipts – put great strain on our public services.

The Office for Budget Responsibility has shown that we would need to borrow an additional £16 billion by 2020 to make up for the reduced tax take from falling migration, with a further cost of £8 billion every year thereafter. And the government's own secret Brexit impact analysis, leaked last week, sets out clearly the cost to the British economy of cutting migration from the EU.

Those who support the government's policy talk in Delphic terms about how the economy will 'adjust' and how businesses will 'adapt'. Our report acknowledges that what this actually means is higher prices for consumers. But even we fail to say that these 'adaptations' and 'adjustments' will too often be reduced production, diminished competiveness or increased mechanisation – in all cases meaning fewer jobs.

At a time when it’s so vital for the UK to remain a globally dynamic economy reaching out to the world, the national interest requires politicians of all parties to speak the truth, and to have the courage to make the positive case for immigration. This includes those who support continued membership of the European Union, as I do, who now need to make a strong positive argument for the continued free movement of people to and from the EU, rather than accepting the characterisation of this as a 'price worth paying' for single market membership.

It remains the case that the greatest hostility to immigration – and the greatest support for reducing it – is to be found in those parts of our country where there are fewest immigrants.

Despite politicians of both main parties advocating immigration control in order to solve the problems of these areas, the reality is their problems won’t be solved in this way – despite the promises made to them – because their problems were never caused by immigration in the first place.

We will therefore damage our economy by leaving the single market, only to find that the supposed political dividend of control was itself a fiction.

In this gap between expectation and reality, the politics of extremism lies in wait.

There is now an urgent need to change the terms of debate, focusing not on offering false solutions or raising expectations that can never be met, but instead on seeking genuine solutions to the very real problems the people of this country face.

Lord Livermore is member of the economic affairs select committee, a senior fellow at the LSE and a former strategy advisor for the Treasury and No.10.

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