By Molly Scott Cato

Earlier this year, a leaked Department of Health study revealed that a hard Brexit would leave the NHS short of 40,000 nurses by 2026. This led me to write to Brexit secretary, David Davis, demanding the government urgently disclose any other findings into the potential impacts of the hard Brexit path it is pursuing.

The response from the Department for Exiting the EU (DExEU) revealed that they have conducted analysis of over 50 sectors of the economy, but no indication was given as to the findings from these studies. So potentially more than 50 secret papers fill the shelves at DExEU offices.

Attempted reassurances in the letter that the DExEU has "travelled up and down the country to listen to the hopes and concerns of businesses, civil society and of course the general public", won't wash. The government is sitting on crucial information that ought to be in the public domain. It could help determine future policy on key issues such as membership of the single market and customs union, freedom of movement and the rights of EU nationals.

Of course, DExEU aren't alone in carrying out research or listening to those on the receiving end of the government's hard Brexit plans. There has been a veritable flood of studies indicating what an economic disaster awaits us if the government pursue its preferred hard Brexit route. If the government's own studies contain anything to counter this overwhelmingly pessimistic outlook, why have they not been released? We can only conclude that either the government is running scared of its own extreme form of leaving the EU, or it wants to keep a lid on the dire consequences of it.

It's probably safe to assume therefore that the government's own analysis agrees with a recent Local Business Survey. It showed that of 419 small and medium sized enterprises surveyed in the South West of England, 57% of exporters believed the impact of leaving the single market will be 'negative' or 'very negative'. This compared with just ten per cent who think the impact will be 'positive' or 'very positive'. Or a recent study from the Centre for Economic Performance that examined the negative impacts of trade barriers. It predicts that under either a soft or hard Brexit scenario, leaving the EU will have a devastating impact on the economic performance of our towns and cities.

My own discussions with Honda in Swindon confirmed to me the importance of membership of the customs union. The car industry is heavily reliant on tariff-free trade across the EU and leaving the customs union would disrupt supply chains by requiring time-consuming checks and paperwork for components that currently pass across open borders.

Perhaps it was the terrible findings of their own secret studies that led Philip Hammond and Liam Fox to agree a truce over a transition period for leaving the single market and customs union. But Hammond knows better and has simply capitulated to the hard Brexiteers. While he was foreign secretary, and before the referendum, he oversaw a comprehensive 'balance of competences review', an extensive analysis of the UK's relationship with the EU. On the single market the review concluded that 'the GDP of both the EU and the UK are appreciably greater than they otherwise would be, thanks to economic integration through the Single Market' and that 'integration has brought… appreciable economic benefits.'

The government argues that publishing the most recent studies it has carried out on the impacts of Brexit would undermine its ability to negotiate the best deal for Britain. More likely is that it would reveal what the government doesn't want people to hear: a hard Brexit will be a disaster for our economy.

Of course, Labour as the official opposition, should be piling on the pressure for these sectoral studies to be released. But they are following the Tories to the hard Brexit cliff edge. So any findings that suggest leaving the single market or customs union would be an economic disaster, could prove equally embarrassing for a Labour leadership that is wedded to exactly the same hard Brexit policies as the Tories. The findings could prove particularly uncomfortable given that only four per cent of Labour members actually favour leaving the single market.

It is in the public interest that the Brexit process is as open and transparent as possible. I have therefore written again to David Davis requesting he disclose the key findings of the sectoral analyses carried out by the government. If he fails to do so I will begin a Freedom of Information request.

There can be no place for David Davis' "constructive ambiguity". Now more than ever, communities, businesses and public services need confidence in our long-term planning and this can only be achieved through open, transparent decision-making.

Molly Scott Cato MEP is Green party speaker on Brexit and on economics

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