John Mann MP: Jacob Rees-Mogg is undermining Brexit

Brexit-supporting Labour MP John Mann calls for a sensible, reasoned debate and tells his former Select Committee colleague "It’s time to stop insulting officials".



Well-spoken and smart-suited, few would take Jacob Rees-Mogg for a fool. Yet it takes a fool to come out and talk down our world-class, hard-working and famously impartial Civil Service who cannot use the media to defend themselves. It takes a greater fool still to have spent last week undermining Brexit every time he opened his mouth.

Last week, Rees-Mogg accused the Treasury of deliberately manipulating the Brexit impact assessments for political ends. He was unusually plain in his assessment, accusing the Treasury of ‘fiddling the figures’.



This was part of a wider attack by leading Tory Brexiteers to talk down the civil service. Brexit Minister Steve Baker found himself forced to apologise to the House of Commons for backing up Rees-Mogg’s misleading claims about Think tank Director Charles Grant having deliberately developed a model to accentuate the downside and that “officials intended to use this to influence policy”.



Rees-Mogg and Baker are wrong to be looking to the Civil Service for Brexit-blocking bogeymen. One of the best arguments for Brexit was that the strength of our institutions, our judiciary and our civil service that would mean Britain could thrive outside of the European Union. Attacks on these institutions undermine this case, rather than strengthening it. Like Jacob Rees-Mogg, I am a strong supporter of Britain’s decision to leave the European Union. However, I also believe that the positive case for Britain’s decision to leave is sadly absent from our public debate.



Having a sensible, reasoned debate on the detail is the only way that the positive case for Brexit can win the day. Ideological assertion and straw man arguments undermine Brexit more with every passing day.



Economic models are only as good as the data you feed in, the assumptions you make and the confidence with which the statistics should be interpreted. Even Jacob Rees-Mogg acknowledged this point last week saying that “with all forecasts, the assumptions you make at the beginning determine the outcome you get”. Yet, he failed to follow through on this and question the assumptions.



Having a proper debate about the Brexit impact studies requires analysing these, and this is why I believe MPs—and the wider public—should have access to them.



So far, the public debate has focussed on the headline outcome shown by the impact studies. All we know for sure is that if all the assumptions made by the Treasury turn out to be correct and their data in every part of the model is accurate, then over a range of outcomes we would expect a drop of a few percentage points in economic growth after fifteen years.



Yet, the independent Office for Budget Responsibility’s Economic and Fiscal Outlook shows us exactly how to make a reasoned argument against the impact studies.



Firstly, it states the basis on which many claims about immigration were made. The OBR’s Robert Chote told the Treasury Select Committee late last year that they estimate net migration falling from 265,000 per annum to 165,000.



Yet the Treasury’s assumptions on migration are flawed, believing that every incoming migrant always contributes a net economic gain to the UK. After Brexit— if we secure the kind of deal I want to see—we will have more power over the mix of migrants coming in. High-skilled migrants working in sectors where home-grown workers lack the skills contribute sufficiently to the economy to outweigh their use of the NHS and other public services.



Second, forecasting so far ahead is famously fraught with difficulty and uncertainty. To quote from the OBR as late as November, “given the uncertainty regarding how the Government will respond to the choices and trade-offs it faces during the negotiations, we still have no meaningful basis on which to form a judgement as to their final outcome and upon which we can then condition our forecast”.



If even the OBR lack confidence in their ability to forecast accurately so far ahead and with so much left unknown, there are reasons to doubt how sure we can be in the statistics.

I served alongside Jacob Rees-Mogg on the Treasury Select Committee. As a former city trader, he is impeccably well informed about the perils of interpreting forecasts and not unpicking the reasoning behind them.



It is no secret that Rees-Mogg is courting the right of the Tory Party to talk up his leadership bid. But deliberately attacking civil servants and ignoring the detail of the argument should win him no friends among those of us who want a reasoned debate leading to a sensible exit deal.



If Jacob Rees-Mogg is serious about advocating for Brexit rather than just advocating for Jacob Rees-Mogg, he will realise it’s time to stop insulting officials. I am sure that with his considerable intellect on the case and the studies out in the open, we will soon get to the bottom of the flawed assumptions behind the figures. For now, his posturing is in serious danger of destabilising Brexit.



John Mann is the Labour MP for Bassetlaw and a member of the Treasury Committee