The judgment of the Supreme Court in R (Miller) v Secretary of State for Exiting the European Union required the government to seek parliamentary approval (through legislation) for the triggering of Article 50, which formally started the Brexit process. In this post, Mark Elliott, Jack Williams and Alison Young argue that parliament has failed to capitalise on the court’s decision and that it is the executive, not parliament, that is truly in control of the Brexit process.

Whether you like your Brexit ‘hard’, ‘soft’, or ‘red, white and blue’, one thing is clear – this will be the executive’s Brexit. Despite the Supreme Court decision in Miller handing parliament a golden opportunity to shape Brexit, Theresa May’s government has been in the driving seat, largely unimpeded, ever since the 2016 referendum in favour of leaving the EU. Parliament has consistently been a passenger.

The first pitstop on the executive’s journey to Brexit was the triggering of Article 50. As is by now well known, the government claimed that it already had the power to trigger the process of the UK’s leaving the EU by virtue of its foreign relations prerogative. Indeed, the government’s initial intention was to trigger Article 50 by the end of 2016, necessitating an expedited process in the Miller litigation, leapfrogging the Court of Appeal to ultimately reach the Supreme Court by the end of the year. If one believes that the triggering of Article 50 (in March 2017) was premature, then it is troublesome to imagine what would have happened if, in the absence of the litigation, it had been triggered six months earlier.  

The Supreme Court came down firmly in favour of parliament, ruling that the government would be able to initiate Brexit only if parliament were to empower it to do so, albeit that the UK parliament could lawfully go ahead and authorise the triggering of Article 50 whether the devolved legislatures liked it or not. This was on the basis that the foreign relations prerogative does not extend, by its very nature, to changing or affecting domestic law or rights. At the time, Miller therefore appeared to be of immense political significance because it put parliament so firmly in the Brexit driving seat. However, 18 months on, the picture looks rather different, and the judgment has proven to be far from the final word on the underlying controversies.

The real significance — or, more accurately, the true potential — of the case concerned not whether Brexit happened, but by what process, and by whom, the meaning of Brexit would be determined. By deciding Miller as it did, the Court handed parliament a golden opportunity to shape Brexit. Whilst the referendum was politically significant, the supremacy of parliament was upheld: only with its authority could Article 50 be triggered. But the opportunity was squandered almost immediately, for fear that parliamentarians would, as some of the judges involved in Miller had been, be cast as enemies of the people. Legislation was enacted hot on the heels of the judgment, handing the Prime Minister the broadest of bare powers to trigger Article 50 at the time of her choosing, and – despite efforts by the Lords – without any conditionality or parameters for negotiations.

What might parliament have done instead? It could have allowed the government to trigger Article 50 only once it had obtained parliamentary approval of its negotiating objectives. This would have ensured that such objectives actually existed prior to the two-year countdown to Brexit commencing and that they commanded the support of a majority of parliamentarians. None of this would have thwarted ‘the will of the people’ — who were asked only whether the UK should leave the EU, not what its future relationship with the EU should be — and would have avoided the current situation, in which less than a year from exit day, it is unclear whether the UK’s negotiating position (to the extent that it can be discerned at all) commands the support of the majority of the governing party, let alone parliament.

Whilst Miller may be seen as a victory for parliament over executive power, the same cannot be said for the European Union (Withdrawal) Act 2018. With its focus on the post-Brexit domestic legal landscape, this might be thought of as the second pitstop on the road to Brexit. That the Act represents no victory over the executive is particularly apparent in regard to the broad sweeping powers given to the executive in order to remedy so-called deficiencies in domestic law arising from withdrawal and to implement the withdrawal agreement prior to exit day – should any agreement be reached in time. These powers are particularly problematic given that they include wide Henry VIII clauses, enabling delegated legislation to modify and amend primary legislation. Although the Act contains some limits on these powers, and provides for committees designed to determine when greater parliamentary scrutiny is needed over delegated legislation, there remain grave concerns as to the extent to which leaving the European Union could transfer power from parliament to the executive, as well as from the devolved nations to Westminster.

Parliament had attempted to assert some degree of control over the Brexit negotiations by adding provisions to the Withdrawal Act requiring a so-called meaningful vote. Whether those provisions really deliver is very far from certain. While the Act prohibits the ratification of any Withdrawal Agreement in the absence of parliamentary approval, a refusal by parliament to sign off would most likely precipitate a chaotic, ‘no deal’ Brexit, thus rendering the ‘meaningful vote’ little more than a fait accompli. Parliament’s role in, and say over, the future trade agreements (or, perhaps more appropriately, the saving of the old ones which the UK enjoys pursuant to its EU membership) is similarly restrained in the Trade Bill which passed through the House of Commons relatively unscathed.

The referendum campaign in 2016 was run largely on a promise to bring back sovereignty. This has manifested itself in irony in two senses.  First, that ‘the will of the people’ in the 2016 referendum itself has seemingly paralysed Members of Parliament who at each stage since have voted to give the government broad discretions with little, if any, parliamentary oversight. The UK’s famously ‘unwritten’ constitution is a tapestry of legal rules, fundamental principles and political understandings, the delicate fabric of which has been placed under considerable strain. The referendum made it nigh on politically impossible for parliament to capitalise on the opportunity that the Miller judgment afforded. It was also used to justify overriding established conventions governing the relationship between the UK’s constituent nations. And ‘the will of the people’ is played as a trump card that distorts and closes down political debate even though, given the rudimentary nature of the referendum question, it more accurately resembles a blank canvas upon which politicians can, and do, paint at will.

The second irony is that the sovereignty being ‘restored’ is, in truth, not that of parliament, but of an ever-powerful (though perhaps unstable) executive. Whilst in a legal sense, the Supreme Court in Miller was surely correct that the executive is the junior partner in the UK constitution, the practical is not always easy to square with that statement of principle. It is now some considerable time since Lord Hailsham famously warned about the dangers of an ‘elective dictatorship’, but the Withdrawal Act, at the very least, suggests that vigilance in this regard remains imperative.

As we comment in our joint contribution in The UK Constitution after Miller: Brexit and beyond, the Miller case may have been the first major piece of litigation concerning Brexit, but it will not be the last. The Miller case merely concerned the beginning of the Article 50 process: how, consistent with domestic constitutional requirements, the process of departure from the EU was to be initiated. Many unresolved and contentious issues remain, of both a legal and a political character. The key question at the heart of Miller merely concerned the decision to open the door: questions remain as to how far that door should be opened, whether it can or should be closed again, and what lies behind it. What the contributions to The UK Constitution after Miller: Brexit and beyond demonstrate is that the initial process of opening the door has itself raised fundamental legal questions for the UK’s domestic constitutional framework, concerning matters as diverse as the nature of prerogative powers, the nature of parliamentary sovereignty and representative democracy, the relationship between international and domestic laws, the separation of powers and the respective roles of the branches of the UK constitution, the territorial constitution and devolution arrangements, and the nature of constitutional adjudication.

The judicial resolution of those questions in Miller has had significant and no doubt long-lasting implications and effects on that constitutional framework, regardless of whatever ‘type’ of Brexit (if any) is eventually effected. What the political developments since the case demonstrate, however, is that, whatever its form, Brexit will be the executive’s Brexit.

The UK Constitution after Miller: Brexit and beyond, is available now from Hart Publishing.

About the authors

Mark Elliott is Professor of Public Law at the University of Cambridge and co-editor of The UK Constitution after Miller: Brexit and beyond.

Jack Williams is a barrister at Monckton Chambers and co-editor of The UK Constitution after Miller: Brexit and beyond.

Alison Young is Sir David Williams Professor of Public Law at the University of Cambridge and co-editor of The UK Constitution after Miller: Brexit and beyond.