The Brexit Litigation: Statutory Interpretation and the Prerogative

Paul Daly July 25, 2016

As is well known, the people of Britain voted to leave the European Union on June 23. Quite how that vote will shape Britain’s future relationship with the EU remains unpredictable. One important factor is whether and when Article 50 of the Treaty on the European Union will be triggered. There has been a flood of considered academic commentary on this question. In this post, I add modestly to the deluge by suggesting that the outcome of the current Article 50 litigation will, for the most part, turn on the interpretation of the European Communities Act 1972 but might also require a reference to the European Court of Justice. That this is likely to be a matter of statutory interpretation has two important implications: the matter is justiciable but resolving it will require the courts to have regard to a variety of contextual considerations, which in turn may well be influenced by competing visions of the UK Constitution.

As is well known, Article 50 sets out the procedure by which a member state can leave the European Union; in particular, Article 50 provides for a two-year time period within which a departure can be negotiated and at the end of which the member state will leave the EU. During the referendum campaign, Mr. Cameron had indicated that he would invoke Article 50 immediately after a LEAVE vote. In the event, however, he declined to do so, leaving the responsibility in the hands of his successor, Mrs. May.

Now there is an additional complication. Several groups of citizens, who have retained leading members of the bar, have sought declaratory and injunctive relief against the government. Their argument is that only Parliament, not the executive acting alone, can authorize the triggering of Article 50. This might be seen as a cynical move to use law to disrupt the ordinary functioning of the political process, but it might also be seen as a virtuous attempt to require individual members of Parliament to exercise independent judgement à la Edmund Burke about the reformulation of Britain’s relationship with the EU. Regardless, the matter has now been set down for argument in October. An appeal by the losing side to the UK Supreme Court is inevitable.

The argument for the government is quite straightforward. In the Westminster constitutional tradition, international and domestic obligations exist on two different planes. Membership of the EU depends on Britain’s accession to the Treaty (in truth, a series of individual treaties over the years, now consolidated in the Treaty on the European Union and the Treaty on the Functioning of the European Union). Accession was effected by the prerogative power, exercised by the executive, to enter into international agreements.  The prerogative also covers the withdrawal from international agreements and thus includes the capacity to trigger Article 50. Accession to and withdrawal from international agreements occur on the international plane and accordingly fall within the prerogative power over international relations. The European Communities Act 1972, through which Parliament gave effect to these international obligations, exists solely on the domestic plane and does not preclude exercising the prerogative to trigger Article 50 and a withdrawal from the EU. There are additional variations on this argument which locate the power to trigger Article 50 in various statutory sources (see e.g. here), but the prerogative argument is the dominant one.

The argument on the other side is also relatively straightforward. By enacting the European Communities Act 1972, Parliament manifested an intention that the UK become a member of the EU and, more importantly, that rights derived from EU membership should have direct effect as a matter of domestic law. Individuals may rely in UK courts on the rights contained in the Treaty and in some forms of EU legislation. By withdrawing from the Treaty, the executive would be using the prerogative to frustrate the intention of Parliament and to eliminate a significant number of individual rights. One could usefully contrast the position of EU law with the position of the EU Convention on Human Rights, an international instrument that has been incorporated into domestic law by the Human Rights Act 1998. Britain could withdraw from the Convention and by doing so would deprive individuals of their ability to seek relief from the Convention courts — but this exercise of the prerogative would take place solely on the international plane, while the Human Rights Act 1998 would continue to have full force and effect in domestic law, such that the intention of Parliament would not be frustrated at all.

Resolving this argument about the scope of the prerogative is essentially a matter of statutory interpretation. What is the intention of Parliament in respect of the EU and has it qualified the executive’s ability to exercise the prerogative? Consider s. 2(1) of the European Communities Act 1972:

All such rights, powers, liabilities, obligations and restrictions from time to time created or arising by or under the Treaties, and all such remedies and procedures from time to time provided for by or under the Treaties, as in accordance with the Treaties are without further enactment to be given legal effect or used in the United Kingdom shall be recognised and available in law, and be enforced, allowed and followed accordingly…

Distilled to its essence, the argument for the government is that “Treaties” in s. 2(1) means those international agreements to which Britain is a party by virtue of the exercise of the prerogative; once Article 50 is triggered and the two-year period for withdrawal expires, there is nothing left for s. 2(1) to ‘bite on’. Nothing in s. 2(1) restricts the scope of the prerogative; by contrast, s. 2(1) is premised upon exercises of the prerogative that would define the “Treaties”. The argument on the other side is that s. 2(1) manifests a parliamentary intention to enter the EU “Treaties” and give them effect in domestic law; withdrawal from the EU is inconsistent with the ongoing commitment of s. 2(1) to give EU law domestic effect. If I am correct that this is essentially a matter of statutory interpretation a number of important points follow.

First, contextual considerations will influence how courts interpret the statute (and, for that matter, important precedents such as Rees-Mogg). One might reasonably say that the prerogative can only be qualified by clear statutory language. But what is “clear” requires interpretation. This is where the legal and political constitutions might well come into conflict. On the one hand, exercising the prerogative in this matter would override fundamental rights (including those in the EU Charter) by executive fiat, fundamental rights moreover that Parliament has expressly incorporated into domestic law. On the other hand, the executive is responsible to Parliament, the prerogative must accordingly be given a wide scope and because s. 2(1) does not set out to limit the prerogative to enter into and withdraw from international agreements, it would disrupt orthodox constitutional arrangements to require legislation to authorize withdrawal from the EU. Whether judges will come down on one side or the other of this argument may well depend at least in part on their view of the UK Constitution, primarily characterized by legal constraints and due process from one perspective, but by public accountability and the political process from another.

Second, it is unlikely that concerns about justiciability will motivate the courts to refuse to decide the case. If an individual were seeking to impugn the rationality of an exercise of the prerogative — for instance because it frustrated a legitimate expectation — then a court might well respond that judicial review or certain grounds of review are unavailable. Indeed, even if Article 50 were to remain untriggered for a considerable period of time, a court would be unlikely to compel the government to trigger it at the instance of a frustrated LEAVE voter. However, this case turns on the scope of the prerogative and the interpretation of the European Communities Act 1972, matters courts are well-placed to adjudicate.

Third, the effect of Article 50 is very important. If, as some have said, triggering Article 50 does not set an irreversible process in train but the UK could halt or cancel its withdrawal from the EU, then the government’s position in the Brexit litigation is likely to be unassailable because triggering Article 50 would not have the effect of frustrating the intention memorialized in the European Communities Act 1972. However, although whether Article 50 can be triggered by the prerogative or requires statutory intervention is a question of domestic constitutional law for the UK courts to answer, whether Article 50 is revocable is a question of EU law. This means that a reference to the European Court of Justice could be required in order to resolve the domestic litigation (unless the government were to prevail on the interpretation of the European Communities Act 1972). This would create additional delays before the UK courts could conclusively answer the important questions of domestic constitutional law raised by the Brexit litigation.


Updated the July 25, 2016 at 08:53.