Canada: Parliament Must Trigger Brexit - The High Court Decision In Miller And Dos Santos

The Divisional Court has this morning (3 November) handed down the judgment in Miller and Dos Santos v Secretary of State for Exiting the European Union.

In a unanimous verdict, the Court determined that the decision to trigger Article 50, and so to begin the process that will lead the UK out of the EU, is for Parliament to make. The government cannot, as it had argued, use its prerogative powers to do so.

Here, we consider the first instance judgment in one of the most important constitutional cases ever to come before the UK courts.

Background and issues

The process for leaving the EU is set out in Article 50 of the Treaty on European Union.

Under this, a member state must make a decision to withdraw from the EU in accordance with its own constitutional requirements (Article 50(1)) and, having done so, notify that decision to the European Council (Article 50(2)).

That notification serves to commence a two year period (extendable only by unanimous consent) during which the UK negotiates the terms of its withdrawal from the EU.

The government's position is that the result of the EU referendum held on 23 June 2016 constitutes a decision for the purposes of Article 50(1) and that, following this decision, the government may use its prerogative power to give the notification under Article 50(2). On this analysis, that notification will simply be an administrative act following on from the decision already taken. In the alternative, the government argued that it could use the prerogative to make the decision to leave in any event.   

As we have outlined in a previous alert, the two individual claimants in this case are Gina Miller and Deir Dos Santos. They were joined by a supporting cast of interested parties and interveners.

The Claimants and the interested parties disagree with the government's position, with most arguing that an Act of Parliament is necessary before notification under Article 50(2) may be given.

This, they argue, is because prerogative powers are not available where their use would frustrate the will of Parliament as outlined in statute. In this case, the European Communities Act 1972 (the ECA) gave domestic effect to a range of rights under EU law which would cease to be available once the UK left the EU. Although some of those rights (such as employment rights) could be replicated in UK law, others (such as the right to free movement throughout the EU) could not. The giving of the Article 50 notice by the government would therefore pre-empt any ability of Parliament to decide on whether those statutory rights should be changed.

The Claimants also argue that, although Parliament will have an opportunity to decide whether or not to ratify any withdrawal agreement negotiated with the EU, this will not cure that pre-emption as, by that point in time, it would not be possible to reverse the UK's withdrawal from the EU. Importantly, the government conceded the issue of the irrevocability of an Article 50 notice. 

In the words of the Court: "Once the notice is given, it will inevitably result in the complete withdrawal of the United Kingdom from membership of the European Union and from relevant Treaties at the end of the two year period" (subject only to any extension of this timetable).

The Court's determination

The Court – comprising the two most senior judges in England and Wales (the Lord Chief Justice and the Master of the Rolls) together with Lord Justice Sales – found for the Claimants.

The Court took as its point of departure the government's contention that the content of the rights given effect by the ECA is defined by reference to the EU Treaties. On the government's case, Parliament had intended the continued existence of those rights to be conditional upon the UK's continued membership of the EU, and that membership depends on the actions of the Crown on the plane of international law. 

The argument was therefore that, absent any express wording constraining the use of the prerogative, the intention of Parliament in the ECA was actually that EU rights would at any time be vulnerable to action by the government.

The Court, in a unanimous judgment, considered that this went much too far. As a matter of law, there must be express language, or a clear necessary implication, that Parliament has intended a statute to depart from important constitutional principles.

In this case there were two major constitutional principles in play – 

  1. that the Crown cannot use its prerogative powers to alter domestic law, and 
  2. that the Crown's prerogative power operates only on the international plane.

With respect to the first principle, the Court highlighted that the ECA has a special status, as one of a small number of 'constitutional statutes', which are exempt from the usual doctrine of implied repeal (under which a statute can be taken to be repealed simply by virtue of its inconsistency with a later statute). Given that status, and the insulation it provides from implied repeal by Parliament itself, it could not be thought that Parliament had intended that the legal effects of the ECA could be removed through use of executive action by the government.

With respect to the second principle, the Court held that the government is certainly free to use the prerogative on the international plane. However, the reason why this is the case is precisely because in doing so it has no effect on domestic law. Where – as in this case, because of the ECA – an action on the international plane would affect domestic law, it lies outside the scope of the prerogative.

Against this background, the Court considered that it was clear that Parliament had intended to legislate in the ECA to introduce EU law into domestic law in such a way that it could not be undone through use of the prerogative. The government therefore has no power to effect a withdrawal from the EU by using the prerogative to give notice under Article 50.

This decision is plainly the right one for the reasons we outlined back in July. 

It is interesting to note the comments made by the Court regarding the decision of the Northern Ireland High Court in the parallel proceedings held in Belfast (McCord's (Raymond) Application). As we have previously discussed, in McCord the High Court was considering only arguments related to the Northern Ireland legal context and, in particular, the effect of the Northern Ireland Act 1998. However, the Divisional Court in Miller and Dos Santos pointed to some errors in the McCord judgment, some of which sprang from the different way in which the two cases were argued. Those comments may give impetus to an appeal by the applicants in McCord.

Next steps

The government has confirmed its intention to appeal the judgment in Miller and Dos Santos.

The case will now be subject to a leapfrog appeal to the Supreme Court (where it may be joined by McCord) under sections 12 and 13 of the Administration of Justice Act 1969. At this morning's hearing, James Eadie QC, on behalf of the government, applied for and was granted the certificate that is the first step in that process.

This will be followed by an application to the Supreme Court for formal permission regarding a direct appeal to it. Permission will certainly be granted and the Supreme Court has already set aside some time in early December to hear the case with a view to issuing a decision before the end of the year.

The decision by the Divisional Court is therefore a dress rehearsal for a Supreme Court determination in December. However, the judgment, made by a bench including two of the most senior judges in England and Wales, may well set the weather in the Supreme Court and make an eventual victory for the Claimants more likely. 

If that happens, the Prime Minister's plan to trigger Article 50 by the end of March next year will probably need to be abandoned and MPs will have a chance to impose conditions ensuring proper Parliamentary scrutiny of the negotiations as they go forward. That is important as such scrutiny has been sorely lacking to date.  

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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