As the author of Article 50, this is why the UK needs a final say on the Brexit deal

If it made sense for parliament to ask the people for their view on the principle, it makes sense to give them a say on what Brexit would mean in practice

More than two years since the 2016 referendum, a political, economic and possibly constitutional crisis is gathering across the United Kingdom. The most viable and democratic way of resolving it is to allow the public to have the final say on Brexit. To deny them a voice challenges the basic principle of informed consent.

People want the right to decide. Polling by YouGov this summer has demonstrated clear backing, by 45 per cent to 35 per cent, for a public vote on the outcome of the Brexit negotiations. This rises to a margin of two to one – 50 per cent to 25 per cent – if talks break down and the UK leaves without any deal.

Such levels of support have inevitably raised questions about the feasibility, legality and practicality of delivering a referendum. This is a further sign of how people from all parties and of none, including many who previously opposed a people’s vote, are now turning towards it as the best – if not the only – way forward.

Today, for the first time, the People’s Vote campaign is setting out a clear roadmap. Drawing on discussions with constitutional and legal experts, as well as politicians, in the UK and elsewhere in the EU, our report makes clear the die is not irrevocably cast. There is still time and, until the UK has left the EU, the Article 50 letter can be withdrawn.

We argue that, if there is a majority in parliament for a people’s vote, there will be at least six plausible routes to securing one. It is also clear from our conversations with politicians and officials from across Brussels and key European capitals that should the UK need more time for a people’s vote, the other 27 member states would agree the necessary extension of the Article 50 timetable.

Then there is the question of what options should be on the ballot paper. The simplest solution would be a binary choice on the ballot paper, either “no deal versus stay” or “the deal versus stay”. In our view, if there is a deal, the most pressing question for the country would be whether that deal is better than the one we have already inside the EU. And if there is no deal, the country deserves the right to say whether it nevertheless still wants Brexit.

However, we recognise there are arguments in favour of other formulations and we do not entirely rule out, for instance, a referendum with three options if it could command majority support in parliament. But, for reasons of simplicity, speed and clarity, as well as past experience, it is unlikely such a proposal would prevail.

The public has as much right to a final say on the outcome of the Brexit negotiations as on the question in the 2016 referendum. If it made sense for parliament to ask the people for their view on the principle, it makes sense to give them a say on what Brexit would mean in practice. Indeed, it is arguably more important that the people should vote on what lies ahead, when the consequences have become clearer, than before any of them were known.

Indeed, to waste time or to do nothing are perhaps the worst options of all. History will not, in my opinion, be kind to any politician who hides behind purely logistical arguments, legalese or arcane parliamentary procedure in order to deny people a vote on the outcome of the Brexit negotiations at such a fragile and crucial moment for our country.

Lord John Kerr is the author of Article 50, former ambassador to the US and former permanent representative to the EU