Thirteen months may have passed since the EU referendum, but I have never felt more concerned than I do today about my party’s position on the biggest issue facing our country.

My colleague Barry Gardiner’s contribution to the Brexit debate, in which he argues for the UK to come out of the single market and customs union to facilitate Brexit was, for me, depressing and disingenuous in equal measure.

I like Barry. He’s intelligent and witty – but I think he is fundamentally wrong on what Labour’s Brexit policy should now be.

He starts by asserting the reasons he says people voted for Brexit last year – a list that could have come straight out of Tory Central Office – sovereignty, immigration and the European court of justice. But what about the false promise of large amounts of extra money for the NHS? What about the British prime minister who hyped up his negotiations with the EU but came back with very little to show for it? What about the sense among low- and middle-income earners that there just had to be something better than the longer hours and squeezed household budgets they were experiencing after the 2007 financial crisis? If just a tenth of those who voted to leave last year voted for these reasons, the course on which the government is now set (and which Labour will be supporting if we sign up to coming out of the customs union and single market), will not be a course that either enjoyed majority support in June 2016 or that enjoys such support now.

“We will become a vassal state if we stay in the European Economic Area”, is the next of Barry Gardiner’s arguments – we become a rule taker and not a rule maker. I would rather we stayed in the single market by staying in the EU, but if it’s a choice between queues outside Lewisham job centre and queues of lorries at Dover or an argument about democratic purity in decision-making, I know which one I would take.

In any event, it isn’t as clear cut as he suggests. Countries in the European Economic Area already participate in the preparation of EU legislation relevant to them. They have a hold-out power, ultimately underpinned by the ability of their sovereign parliaments to reject any proposed EEA legislation. Yes, those EEA countries are comparatively small compared to the EU member states. But were the UK to become a non-EU member of the EEA, the current imbalance in administrative resources that exists between the EU and EEA states would be markedly less acute – in all likelihood, strengthening the hand of the EEA members. I know it’s not perfect, but it’s better than the economic alternative.

As the smaller party in any future trade talks with the EU, we will inevitably cede sovereignty in a future agreement

Furthermore, our relative democratic ability to shape EU law and regulations seems only ever to be a comparison with the status quo and not a comparison with the alternative future outside the single market. As the smaller party in any future trade negotiations with the EU, we will inevitably cede sovereignty in a future free trade agreement. Our businesses will have to agree to meet the standards and regulations agreed by the EU in order to sell into that market. So why is the inevitable ceding of some sovereignty under a negotiated free trade agreement so much better than having a say as part of the EEA? I just don’t buy it.

On to the thorny issue of immigration. Setting aside the fact that the UK already “controls” immigration from countries that account for 90% per cent of the world’s population (a fact not widely repeated in the runup to the referendum last year), those who favour leaving the EEA say it’s the only way to “deal with” freedom of movement.

But is it? Article 112 of the EEA agreement expressly allows a country to limit the operation of any one of the four freedoms – including freedom of movement – if it is able to prove significant economic or social harm. We also know that within the current freedom of movement rules a more robust system would be possible – the requirement to have a job within three months of arrival or to be self-sustaining has never been enforced in the UK, despite more rigorous processes having been adopted in other countries to whom the same rules apply.

We must also ask ourselves whether immigration really is the “issue that needs dealing with” as is so often claimed. In poll after poll, public concern about immigration is falling. When presented with the hard choice – fewer jobs, less business investment, more complicated trade – it seems the British people increasingly agree “economy first, immigration second”. When asked to think about who pays for our pensions in 30 years’ time, who provides vital care in our NHS, or who works in our care homes, a large proportion of the British public understand that we aren’t having the same number of babies as we did 40 years ago, and that immigration frankly holds many of the answers.

And finally to the European court of justice. Yes, the ECJ rules on matters that affect us. But it is a myth to think that if we leave the EU our courts alone will hold sway. Any free trade agreement we enter into will always have some form of dispute-resolution mechanism built into it. In the EU, the European court performs such a role; elsewhere bodies like the WTO or independent arbitral panels opine on how such agreements are to be interpreted. No one gets entirely their own way. So let’s not pretend that an ECJ-free future puts all the power back into our hands.

It was only back in December that Barry was quite rightly mocking arch-Brexiteer and Tory MP Bill Cash by suggesting that he should add “No to prosperity and jobs” to his list of “No to the single market. No to the customs union. No to the European court”.

I agreed with Barry Gardiner then; I’m afraid I don’t now.