Although the headlines record that the government lost the Brexit judicial review in the Supreme Court, in fact it might be more accurate to see the result as a draw. While the government lost on the question of whether the prerogative could be used to trigger article 50 (and will now have to seek legislation to authorise it to do that), the Supreme Court found unanimously (including the two Scottish justices and the Northern Ireland justice) that that the devolution legislation did not require the UK to remain a member of the EU and that the devolved administrations had no veto over the UK’s decision to withdraw from the EU. The devolved administrations will not be happy about this, but a very big can of worms would have opened up had the Court ruled that the consent of the devolved legislatures was required for Brexit. That consent would probably have proved impossible to obtain and Brexit might have been derailed unless or until the sovereign parliament acted and waved the wand of legislation to abolish the devolved legislatures’ veto. But the delays and disputes and vituperation would have been endless and bitter. Those who accept the result of the referendum should be grateful that the Supreme Court followed orthodoxy and held that the conventions requiring in certain circumstances the consent of the devolved legislatures were not legally binding.
Although obviously politically very important, the legal principles applicable to the question of whether an Act of Parliament was required to rigger article 50 were straightforward and uncontroversial. These were (i) the making and unmaking of treaties was a matter for the prerogative and (ii) that the government could not by the exercise of the prerogative powers change domestic law. But which principle overrode the other? In the event the majority of the Supreme Court held that section 2 of the European Communities Act 1972 created EU law as a source of UK law, i.e., domestic law, that could not be changed by prerogative powers. Striking and novel though this is, it is a technical issue on which views might reasonably differ and did differ as the three judgments in dissent showed. But once article 50 is triggered the day will inevitably come on which EU law will cease to be domestic law; it is an issue that will probably never arise again. Miller will stimulate a wave of academic articles but does not really change established constitutional principles.
There is a tension in our constitutional arrangements between representative democracy (expressed though our MPs in Parliament) and popular democracy (expressed though citizens voting in referenda). In Miller, a crucial fact is that no provision was made in the 2015 Act of Parliament providing for the referendum on membership of the EU for what the position would be if the people voted to leave! It “could have saved a lot of fuss” (Clive Coleman’s phrase) if an extra line of text been included in the 2015 Act authorising the government to trigger Article 50. One can only agree and regret Parliament’s silence in 2015! And so now: the battle to pull the Article 50 trigger becomes political not legal.
Christopher Forsyth is Emeritus Sir David Williams Professor of Public Law in the University of Cambridge.
Click here for further analysis of the Supreme Court’s Miller judgment.