UK 25 September 2019 How Boris Johnson’s Supreme Court defeat has changed British democracy for the better Any future attempt by a government to use its power to frustrate parliament’s constitutional role will be unlawful. Getty Images The Houses of Parliament on 24 September 2019 after the judgement of the Supreme Court. Sign UpGet the New Statesman's Morning Call email. Sign-up Boris Johnson returns to the United Kingdom today with his attempt to prorogue parliament rejected and undone by the Supreme Court, who ruled unanimously that he acted unlawfully. Parliament, too, returns from its forced holiday, with opponents of a no-deal Brexit planning a variety of measures to further frustrate Johnson. Does it matter? The government has already been defeated over Brexit in any case. What's the worst that can happen to the Conservative government now? In the short term, it gives MPs the ability to further improve the law they passed to force an extension to the Article 50 process to prevent Johnson finding some loophole or another to get out of his obligations and secure a no-deal Brexit by some nefarious route. The biggest and most important implications have little to do with Brexit, however. The first and most important consequence is that the use of the executive's control over when parliament sits to frustrate parliament's constitutional role has been ruled as unlawful. That prevents a repeat of John Major's early rolling-up of parliament in 1997 to avoid questions over cash for access, as well as undoing Johnson's prorogation. That's a major victory for our elected legislature against our executive that will stand indefinitely. It gives a reprieve to important bills on domestic violence and divorce reform, that the government had stalled on but the large parliamentary majority in favour of both can, if it wishes, now resume the final stages of its passage. The immediate political consequence is to transform the mood music out of Labour conference. Today's frontpages and television bulletins aren't dominated by coverage of Tom Watson's speech, which was only going to cause the Labour leadership a headache. (If it had been booed, it would have been a sign of disunity. If it had been cheered, it would have been a repudiation of Corbyn.) Instead, the last images out of Labour conference are a series of quick clips of a confident Corbyn being cheered to the rafters after calling for Johnson to resign — a huge contrast to the footage of a shell-shocked Johnson returning from New York with his tail between his legs. And that change in the mood music at Westminster may yet filter out to a broader change in the country. As far as the politics of Brexit go, who benefits is simple: it hurts Labour when the question is whether to do Brexit or not, which promotes Johnson as the leader of the Leavers and Jo Swinson as the leader of Remainers. It helps Labour whenever the Conservatives create situations where Corbyn can assert his role as the leader of the largest single parliamentary obstacle to no deal, relegating Swinson and co to the role of a backing chorus. The return of parliament opens up other prizes to the opposition parties too. Johnson continues to face questions about his relationship with Jennifer Arcuri, the model-turned-entrepreneur, and the funds that his mayoral administration handed to her businesses. The oversight committee of the London Assembly is already using its powers to keep the story going and to keep the spotlight on Johnson — the far bigger level of media coverage that will be afforded to the row if MPs use their powers in a similar way means that it might cause real difficulties for the government. What the court's decision doesn't do is create a constitutional crisis or take us towards an American-style system where judicial appointments become intensely political and contested by partisans. Johnson isn't the first prime minister to have his actions thrown out by the United Kingdom's highest court, whether that be since its separation from the House of Lords to form our Supreme Court, or when it sat as the 12 Law Lords in the Upper House. But in the past, a government that was defeated in the Lords had a parliamentary majority and a would often simply pass a law to override its defeat in court. What we're seeing now is not a constitutional crisis but an outgrowth of the fact that the Conservatives did not win the 2017 election. That is wholly different from the American Supreme Court, where US justices have the power to override the act of any elected government, no matter how large its electoral mandate. It's a good and important victory that a party without a majority in our elected parliament cannot act like an administration with one does — whatever the long-term consequences of Johnson's electoral hopes or the resolution to the Brexit deadlock turns out to be. › Labour's housing chief promises to put housing "at the centre" of general election campaign Stephen Bush is political editor of the New Statesman. His daily briefing, Morning Call, provides a quick and essential guide to domestic and global politics. Subscribe For daily analysis & more political coverage from Westminster and beyond subscribe for just £1 per month!