UK Constitutional Law Association

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Christina Lienen: Brexit and the Domestic Judiciary: Some Preliminary Thoughts on the Aftermath of Triggering Article 50

0d84564This week saw the first legal action concerning the constitutional requirements surrounding the Brexit process being initiated. With or without Parliamentary consent, we now know that the two year negotiation period under Article 50 will only be triggered in 2017. Once negotiations have officially started, it is expected that there will be some sort of political agreement on the post-Brexit EU-UK relationship. It will not be until at least early 2019, however, that a clear path towards the disentanglement of these two sophisticated legal orders will fully begin to crystallise. In the worst case scenario, by the end of the two year period we may find ourselves forced to leave without a comprehensive agreement, should it be rejected by the European Parliament (Article 50(2)) or if no qualified majority can be reached in the Council. Here the qualified majority is defined as at least 72% of the members of the Council, with the additional requirement that the votes represent at least 65% of the population of the EU (Article 238(3)b). The UK will not be part of this vote. If there is no agreement with the UK then UK membership would end automatically, unless the European Council and the UK decide jointly to extend this period.

At this stage, it is difficult to predict exactly how the UK courts will adjudicate cases involving EU law in the immediate future. There are three main timeframes: (1) Post-Brexit referendum but Pre-Article 50 notification, (2) post Article 50 notification but prior to conclusion of the withdrawal agreement, (3) post withdrawal disentanglement and replacement of national law from EU law post withdrawal agreement. Under Article 50(3) the Treaties will only ‘cease to apply from the date of entry of the withdrawal agreement or, failing that, two years after the notification’. From that moment in time EU Law (the TEU and TFEU and post Brexit CJEU case law and secondary legislation and decisions) would cease to apply in the withdrawing state. Under the most straightforward view, the UK will be bound by EU law under its international law obligations until the end of the two year period after Article 50 has been triggered. However, I suggest that it is more complicated than that. Firstly, UK courts value consistency and fairness. It is therefore hard to imagine that a case coming to the UKSC a few months before the two year period runs out would be decided giving full effect to EU law where such a decision in a similar case immediately after Brexit could easily be challenged. Secondly, and perhaps more importantly, in some areas it is incredibly difficult to determine what aspects of a legal rule or legal thinking are influenced or created by EU law, and which ones are purely domestic. Grasping and disentangling 40 years of European Union law and domestic law will be, as Mark Elliott puts it, a herculean effort. It is impossible to address these two concerns conclusively in a blog post. Instead, I would like to flag a few issues concerning one particular type of EU legislation that is likely to cause some constitutional struggle – EU Directives.

O’Brien v Ministry of Justice, a case currently before the UK Supreme Court (UKSC), is about the appellant’s entitlement to a pension under the Part Time Workers Directive (97/81/EC) which the United Kingdom had to (and did) transpose into domestic law by 7 April 2000. Counsel for Mr O’Brien argue that the appellant is entitled to have his service prior to the transposition date taken into account for the purpose of his pension calculation. The hearing finish date was the 7th of July 2016; shortly after the result of the referendum was known. At this stage, it is highly unlikely that the UKSC would arrive at a conclusion which gives anything other than full effect to EU Law. There are no direct legal implications of the referendum at this stage. But jump a few years ahead to a fictitious case with similar characteristics and we begin to appreciate some of the challenges the courts will be facing. What if, in the fictitious future case, the UK had not transposed the Directive in question? Under the doctrine of direct effect, famously established by the seminal CJEU judgments of Van Gend en Loos, Costa/ENEL (both featuring on the 50 Problematic Cases list of the Judicial Power Project) and Van Duyn, individuals can rely directly on EU Directives. This is subject to the conditions that (i) the Directive is clear, precise and unconditional, (ii) it is not dependent on further legislation/action by the Member State or the EU, and (iii) the date of implementation has passed. Whilst the UK has a comparatively low compliance deficit of 1%, the average delay of transposing is 11.9 months, which means that Directives are likely to be relied on which the UK will not implement on time (as ministers are figuring out what to do about Directives during the negotiation period in the first place) as well as Directives that will not have been implemented at all (should Parliament choose not to implement Directives passed whilst it was still officially an EU member, or such Directives passed in the negotiation period). This uncertainty may have consequences for public entities subjected to obligations under EU law. Moreover, under the doctrine of indirect effect national courts are required to interpret domestic legislation in light of EU Directives in horizontal situations. Thus individuals and private companies will also be facing a period of legal limbo regarding their obligations under EU law.

Furthermore, it is uncertain whether the continuing applicability of EU law and its disentanglement from domestic law is a matter of national constitutional law or a matter of EU law. If the latter is the case, we could be facing the very intriguing possibility of a preliminary question to the CJEU, given that the doctrines of acte éclairé and acte clair are clearly not applicable. Should EU law govern the transition period leading up to the exit agreement, EU general principles, which are considered equal in their legal value to Treaty articles, would apply. The main candidate to be considered here is the rule of law, which is informed by the substantive rules of legal certainty, the principle of confidence in the stability of a legal situation and the principle of proportionality. The domestic principles guiding us through these issues on the other hand are the UK’s understanding of the rule of law, constitutionalism and parliamentary sovereignty.

In conclusion, due to the disentanglement of EU law and domestic law and considerations of consistency and fairness, it is difficult to predict exactly how the UK courts will adjudicate cases involving EU law in the immediate future. There are three main possibilities for the post-Article 50 legal landscape. The courts will fully adhere to EU Law and apply it as if the referendum and/or Brexit had not happened for a while; they will adhere to EU Law but give partial or complete preference to domestic law where there is a discrepancy; or they will find a way of starting to disregard EU Law altogether. Directives may prove to be particularly challenging in this context due to their legal nature. Besides O’Brien, other cases involving complex questions on EU law, such as a blanket denial of social welfare assistance to Zambrano carers, are currently before the UKSC. The number of court cases involving EU law is likely to increase at all judicial levels in the near future given people’s anxieties about their legal status and rights. Constitutional lawyers have on numerous occasions been intrigued by the legal reasoning of the UKSC in cases involving EU law. I suspect that we will be in for a treat once the Article 50 trigger is pulled. The courts will be the first ones to actually having to deal with the uncertainty caused by the Brexit process – let’s hope that it will unfold in a less dramatic way than what we have seen over the past few of weeks.

Christina Lienen is a PhD Candidate (LAHP) at University College London. She would like to thank Richard Rawlings, Piet Eeckhout and Jeff King for their much appreciated comments on an earlier draft of this piece.

(Suggested citation: C. Lienen, ‘Brexit and the Domestic Judiciary: Some Preliminary Thoughts on the Aftermath of Triggering Article 50’ U.K. Const. L. Blog (21st July 2016) (available at: (available at:

6 comments on “Christina Lienen: Brexit and the Domestic Judiciary: Some Preliminary Thoughts on the Aftermath of Triggering Article 50

  1. richard jarman
    July 21, 2016

    This is NOT a new problem for the UK. We coped with the problem in former colonies (and Eire); independence legislation contained a clause to the effect: “Laws in force before the coming into force of this Act remain in force until repealed by XYZ”. Regardless of any A 50 talks such a provision will have to be enacted, XYZ in this case being the UK parliament.

  2. Anthony Arnull
    July 22, 2016

    This post raises some interesting and important issues.
    The first point to make is that invoking Art 50 TEU does not in itself have any effect on the applicability of EU law in the withdrawing State. So the Treaties would only cease to apply to us on the entry into force of the withdrawal agreement concluded pursuant to Article 50 (this may not be immediate) or, if there is no agreement and no extension, two years after that provision was triggered.
    Up to that point, it seems clear that the national courts should in principle continue to apply EU law in the normal way. However, preliminary references to the ECJ are now taking around 15 months on average before the response is received. Some cases will take longer. This may have a chilling effect on recourse to the preliminary rulings procedure by UK courts from the moment Art 50 is invoked.
    This should be resisted. During the withdrawal negotiations (and any subsequent negotiations to build on the ‘framework for [our] future relationship with the Union’) It will be important for us to comply or have complied with our Treaty obligations in order to secure a the best possible deal. As the negotiations progress, there will be a theoretical possibility that we might change our mind, perhaps after a second referendum. The deal itself may require us to continue to apply certain EU rules. It is not likely to be possible to identify all of these in advance. So our national courts should continue to apply EU law in the normal way until the Treaties formally cease to apply to us. The withdrawal agreement might very well say that references made up to the point of withdrawal will be dealt with by the ECJ.
    This means that no disentangling should take place before that point, although it would be sensible to make preparations for what is to be done thereafter. By then, the ECA 1972 will presumably have been repealed. The resolution of cases after our withdrawal may be affected by the terms of our withdrawal agreement. But if no agreement is reached within the two year period and there is not enough support for extending it, the starting point should surely be that cases will be decided in accordance with the law in force – EU and national – at the material time. It would be for our national courts to say what that was.
    There will also be issues around direct actions. Withdrawal will not affect the capacity of UK nationals to bring proceedings against the Union for annulment, failure to act or non-contractual liability. The position of infringement proceedings with the possibility of sanctions against the UK is more problematic.
    In principle, the Commission may continue to launch such proceedings until the Treaties cease to apply to us. Treating them seriously would help the UK to maintain its negotiating credibility. The imposition of sanctions would not be helpful while negotiations were ongoing and futile once they had come to an end, subject to their outcome. The Commission might be inclined to withdraw any cases that had not been decided by the point of withdrawal and the ECJ might consider them devoid of purpose, unless perhaps they raised an important point of principle. Again the equation might be affected by the contents of any withdrawal agreement.

  3. Stewart Connell
    July 23, 2016

    There is no mandate to activate Article 50.The United Kingdom is a parliamentary representative democracy. The EU referendum was national survey with no authority or mandate contained inside it, check the legislation there is no provision for a transfer of authority into the referendum device. Last years general election returned a House of Commons with a substantial majority in favour of the 1972 European Communites Act including Mr Johnston and MrGove. Nothing has changed. It is fiction.

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