SUMMARY: Gina Miller will be confident of victory as the Brexit legal case comes to an end
It has been four days of vigorous legal debate in Westminster. The 11 justices charged with delivering what will be one of the most significant verdicts in British history probed both sides with searching questions throughout the case.
But, it'll be Gina Miller and the claimants who brought the case against Theresa May's government who will leave the court today with the most confidence ahead of the ruling in early-January.
The High Court was unanimous when it decided last month that May must secure parliamentary approval before triggering Article 50. The government's legal team showed up to the Supreme Court on Monday knowing that it had to convince the justices that their colleagues were all united by an incorrect interpretation of the law.
Attorney General Jeremy Wright QC and James Eadie QC, whose performances in the High Court case were reportedly lambasted by government ministers behind closed doors, had a chance to redeem themselves.
Wright kicked off the proceedings confidently on Monday, raising the point that parliament had numerous opportunities to limit the scope of the royal prerogative powers prior to June's EU referendum taking place.
But Lord Pannick QC, who is representing Gina Miller in the case, once again articulated the investment-manager's objections impressively, reiterating the underlying argument that triggering Article 50 without first consulting parliament would lead to rights which parliament established and only parliament can legislate on being nullified.
As neatly summarised by legal commentator David Allen Green: "Government could still win this - never underestimate the royal prerogative - but it will be a struggle. Government should prepare Bill."
The government's case is far from dead. The Supreme Court justices had raised just as many questions and points of contention with the claimants' case as they did the government's. On Wednesday, Pannick and the bench engaged in an engrossing, back-and-forth game of legal tennis over the 2015 referendum act and the effect it has in law.
Work is undoubtedly already underway on the act of parliament the government will have to put to MPs if the Supreme Court refuses to uphold its appeal. A House of Lords source told Business Insider that parliament expects the government to lose and then table an Article 50 bill as soon as possible. Eadie appeared to confirm this when he said that the "parliamentary solution" to an unsuccessful appeal would be a "one-line" bill.
Many pro-Brexit politicians and right-wing media outlets have suggested the British judicial system is quietly trying to prop-up a pro-EU political establishment. Anyone who watched this week's proceedings unfold would struggle to look at this theory with a straight face, given how rigorously every single lawyer who addressed the judges was put through their paces and examined with no detail spared.
Miller, May, and every other figure who has a stake in this ruling will now wait until the new year to learn the Supreme Court's verdict. If the government loses, MPs will have the opportunity to vote on whether Article 50 should be triggered having learnt more details about the government's negotiating position. If it loses, May will have a clear path to press on with Brexit and "make a success of it" - be it hard or soft; red, white, and blue; or somewhere in between.