UK 24 September 2019 The Supreme Court’s ruling against Boris Johnson shows we need a written constitution It is time for our rights, and the rule of law, to be codified and protected. Getty Images A person dressed as Boris Johnson holds a guilty sign outside the Supreme Court. Sign UpGet the New Statesman's Morning Call email. Sign-up Today’s Supreme Court judgement was a momentous one. Not only did it find that the Prime Minister’s action in proroguing parliament was unlawful, it did so unanimously, with all eleven judges agreeing. Our democracy has been rescued from an assault by the Prime Minister, his adviser Dominic Cummings and their hedge-fund backers. This is a huge indictment of Boris Johnson and his ignore-the-rules approach to government. He should now resign. But this judgement is not just about the abuse of executive power by Johnson. It also demonstrates the serious weaknesses of our uncodified, unwritten constitution which has survived for nearly 350 years but now appears ever more unfit for purpose. Our system has always depended on MPs and the executive being willing to play by the rules. Now we have a Prime Minister with no respect for the rules and a downright contempt for the law. Our constitution is not an arcane matter for lawyers and academics. The crowds outside the Supreme Court and the huge media interest shows that, at heart, it is about who our democracy belongs to. The Prime Minister had told the judges: “The courts have no jurisdiction to enforce political conventions … because those matters are determined within the political world.” In other words, he claimed he can do what he likes. He can close down parliament when he likes and he and his advisers are beyond the law. This is the behaviour you’d expect of a medieval monarch, not a 21st-century prime minister. The Supreme Court rebutted Johnson’s claims, rightly ruling that his suspension of parliament was null and void. We already know how the Prime Minister’s supporters will react, thanks to the chorus of newspapers owned by millionaires living outside our shores. We can expect calls for a “Brexit constitution” that will put the judges in their place by subjecting them to political control as in Trump’s America, undermining our fundamental human rights. In order to defend the principles of our democracy we must resist this. I’m very glad that the Speaker has said parliament will immediately resume. But this, in itself, will not mend our broken system. It is time for a written constitution so that our rights, and the rule of law, are codified and protected. We need a democracy we can all believe in and this means we have to create it ourselves, with a democratic process based on citizen-led assemblies and conventions. We cannot trust the political class to “give” us this democracy – we have to take control. It is the only way to move on and heal our divided country. This is how we begin to transform Britain. › Boris Johnson saves Jeremy Corbyn's conference speech Caroline Lucas is Green MP for Brighton Pavilion. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!