Professor Catherine Barnard, senior fellow The UK in a Changing Europe, said: “The Vote to leave the EU was premised on taking back control to the UK Parliament and courts. The UK courts (the High Court and the Supreme Court) have both said that the UK parliament should take the momentous decision whether to trigger Article 50. This constitutional decision puts the power back into the hands of the representatives of the British people, not the executive. However inconvenient and difficult this makes life for the government, it is an important aspect of control.”
Professor Damian Chalmers, senior fellow The UK in a Changing Europe, said: “Theresa May has repeatedly stated that the referendum gave the British government the job of delivering Brexit. This case was about the truth of that statement. Fourteen of the United Kingdom’s most senior judges have listened, and eleven of them have concluded that it is both wrong and seeks a huge expansion of executive power at the expense of our parliamentary democracy.
“The right answer is that the referendum gave Parliament the political instruction of deciding how to go about Brexit, and how to order her in this regard. The central reasoning was that the executive cannot take away rights protected by Acts of Parliament, and triggering Article 50 does this. It was, therefore, a little surprising to see the language of No 10 unchanged in its response to the judgment, namely that the British government will trigger Article 50 by the end of March. It is Parliament, after all, which now decides and not it.”
Dr Jo Hunt, senior fellow The UK in a Changing Europe, said: “The Supreme Court was always unlikely to find that the devolved parliaments and assemblies’ consent was going to be needed to trigger Article 50 – Westminster Parliamentary sovereignty is so deeply entrenched within all the devolution legislation, and foreign affairs is a matter for central government and Parliament to handle – no parallel powers on withdrawal for the devolved administrations to exercise were recognised.
“The recent placing on a statutory footing in the Scotland (and soon the new Wales) Act of the Sewel Convention (that UK Parliament will not normally legislate on devolved matters without their agreement) has made no difference to the result here. This will disappoint those who believed placing the convention in legislation would give it some bite. The Court’s position here is consistent with its broader approach to respecting Westminster Parliamentary sovereignty – if the convention was meant to be legally enforceable, Parliament would have made sure that was clear in the language used in the legislation.”
Professor Anand Menon, director The UK in a Changing Europe, said: “The Supreme Court judgement puts the ball firmly back in Parliament’s court. It is up to our politicians to decide whether to start the process and what conditions, if any, they will impose on the Prime Minister. Once Article 50 is triggered – which it will be – attention will increasingly turn away from process and towards substantive outcomes. With this in mind, we will be publishing on Monday a set of proposals for how Parliament and the public could hold the government to account for delivering Brexit.”