Churchill spoke, in the aftermath of the Second World War, of a “common citizenship” that would unite Europe together “in the sharing of its common inheritance. [T]here would be no limit to the happiness, prosperity and glory which its 300 million or 400 million people would enjoy.” He urged that we build “a kind of United States of Europe” in which we could “dwell in peace, safety and freedom.”

And the idea of a union of people – and not merely of States – was recognised by the European Economic Community shortly after its formation. In 1963 in van Gend & Loos the Court of Justice rewrote the law of nations by recognising that: “the Community constitutes a new legal order of international law… the subjects of which comprise not only member states but also their nationals… Community law… is also intended to confer upon them rights which become part of their legal heritage.” In signing a Treaty between themselves, the Court found, Member States had given rights directly to the people of Europe.

Our cultural identity as citizens of Europe first took legal form in the Maastricht Treaty of 1992. Today, Article 20 TFEU states that “Citizenship of the Union shall be additional to and not replace national citizenship.” And citizenship gives to us a suite of privileges – the right to live and move freely within the territory of the Member States; the right to diplomatic and consular assistance from other Member States; the right to participate in elections to the European Parliament.

These rights are a gift to 60 million UK citizens. As they are a gift to the other 450 million citizens of Europe.

But what of Brexit? The shared assumption of the European Union and the United Kingdom Government is that it will mean a loss of these rights. But is that assumption right?

The assumption is being tested in a case brought by a group of UK nationals living in Amsterdam and which I funded with the help of Bureau Brandeis – who agreed to act for a modest fee. And earlier this month, Judge Bakels – a one-time Vice President of the Dutch Supreme Court – after hearing argument from both sides said this: “there is reason to doubt the correctness of the interpretation of Article 20 TFEU that the loss of the status of citizen of an EU Member State leads to loss of EU citizenship as well.”

And he decided to refer it to the Court of Justice in Luxembourg – the only court that can decide whether Brexit must means a loss of EU citizenship.

The question can fairly lay claim to being the most important to come before the courts in modern times. If successful, it will make legal history. What other case could grant a suite of valuable legal rights to over 60 million people?

Could the Court of Justice decide in our favour? Could it decide that Brexit does not mean the loss of EU citizenship for UK nationals? That, of course, is a question to which we cannot know the answer.

But what we can know is that a Vice President of the Dutch Supreme Court believes EU citizenship could be retained. And we can know that the Court of Justice has been bold in the past. We know from van Gend & Loos that it sees Europe as a union of peoples giving rights to citizens. It is not just a union of States.

And more than that – there are political leaders here and in Europe who believe the future of the European project is to be found in closing the gap between the Union and its people. There is no better means to that end than recognising that EU citizenship has a status meaningfully “additional to national citizenship,” to borrow the language of Article 20 of the Treaty. And which survives a loss of national citizenship.

But the Netherlands has sought to appeal the decision of Judge Bakels to refer the question to Luxembourg – and we must resist that appeal. And I am crowdfunding for the legal costs – Bureau Brandeis’ legal costs – of defending that appeal.

Our EU citizenship does not replace our national citizenship. But like our national citizenship it is an important part of our cultural and an important part of our legal identity.

Plutarch, in “On Exile”, quotes Hercules:

Am I of Thebes or Argos? Whether

You please, for I‘m content with either;

But to determine one, ‘tis pity,

In Greece my country’s every city.

I am a Londoner. I am British. And I am European. In Europe every state is my country.