The coverage of last Thursday’s High Court judgement on Article 50 has understandably focused on its immediate consequences for the process by which the UK will leave the European Union. However, if upheld by the Supreme Court, it is also likely to have wider constitutional significance. In this post Harmish Mehta explores the implications of one part of the court’s judgement, that the Crown’s prerogative may not be used to unmake a treaty without parliament’s approval if that would change domestic law or diminish the rights of individuals. He suggests that this could mean that the government could not withdraw from the European Convention on Human Rights without parliamentary approval.
Part of the UK constitution is the judgements of its courts of law. Such judgements can have transformative and prolonged effects on UK constitutional practice.
On 3 November, the High Court (‘the court’) handed down its judgement in R (Miller) v Secretary of State for Exiting the European Union ( EWHC 2768), which stated that the executive does not have power under the Crown’s prerogative to give notice pursuant to Article 50 of the Treaty on European Union (‘TEU’) for the United Kingdom to withdraw from the EU [para. 111]). The UK Supreme Court will hear the appeal against the judgement on 5-8 December.
Of course, Miller has a considerable impact on the prospects of the UK exiting the EU in the near future. However, it should not be forgotten that Miller is a judgement of wider constitutional importance. Subject to it being modified by the Supreme Court, it has the potential to shape the UK constitution beyond Brexit. This is partly the consequence of its appeal to, and development of, longstanding and far-reaching principles of constitutional law. It rivals even R (Jackson) v Attorney General ( UKHL 56) in its exploration of the UK’s constitutional history and statements of apparent constitutional truisms.
In this post I will explore the implications of one part of the court’s judgement, which amounts to what I will call, for brevity alone, the ‘unmaking principle’. This principle is that the Crown’s prerogative may not be used to unmake a treaty without parliament’s approval if that would change domestic law, be it statute or common law, in any way, or diminish rights of individuals.
The core strand by which the court came to its conclusion can be split into five stages. The unmaking principle appears in stage two.
First, the court considered immaterial, for the issues before it, the fact that the giving of notice pursuant to Article 50(2) of the TEU does not formally constitute withdrawal from EU membership. The court considered Article 50(2) notice and withdrawal to be effectively equal, primarily because it would ‘inevitably result’ in the UK withdrawing from the EU treaties ().
Second, it held that the Crown’s prerogative may not be exercised in a way which would change domestic law or diminish rights of individuals (). The only exception is where parliament has so authorised (, ). In this context, ‘exercised’ includes any exercise, including withdrawing from, or unmaking, treaties (). ‘Change’ means to change ‘in any way’, including to ‘[strip] of any practical effect’ or ‘[deprive] of any practical application’ (, -). ‘Domestic law’ includes common law and legislation (). It is unclear what the court meant by ‘rights’. At some times it referred to rights created in domestic law (-, , , , , ) and at others to rights generally (, ).
Third, it established that if the executive were to unmake the EU treaties, it would alter domestic law and diminish rights of individuals. Subsection 2(1) of the European Communities Act 1972 (ECA) would be ‘stripped of any practical effect’ and 2(2) would be ‘deprived of any practical application’ (-). A ‘material change’ would also be the loss of the ability to seek authoritative rulings of the CJEU on matters of EU law (). Furthermore, rights of individuals would be diminished ( (category 1 rights),  (category 2 rights),  (category 3 rights)).
Fourth, it found that the ECA, as a matter of statutory construction, cannot be said to have given the executive authority to change domestic law or diminish rights of individuals ().
Hence, and finally, the court held that the executive does not have power under the Crown’s prerogative to give notice pursuant to Article 50 of the TEU ().
The second stage of the judgement and its implications
Stage two of five amounts to the proposition that the Crown’s prerogative may not be used to unmake a treaty without parliament’s approval if that would change domestic law, be it statute or common law, in any way, or diminish rights of individuals. This is what I refer to as the ‘unmaking principle’. This principle has two limbs. The first is that the Crown’s prerogative may not be used to unmake a treaty without parliament’s approval if that would change domestic law. The second is that the Crown’s prerogative may not be used to unmake a treaty without parliament’s approval if that would diminish rights of individuals.
If the UK is party to a treaty and has incorporated it into domestic law, it is very likely that withdrawal would change domestic law, therefore requiring the authority of parliament due to the second limb of the unmaking principle. The unmaking principle is remarkable, in reducing the executive’s ability to act unilaterally to withdraw from many treaties.
Therefore, this gives parliament an important power. When incorporating new treaties in the future, parliament should bear in mind that by making the maintenance of UK law dependent on the UK’s being party to that treaty, it would be setting in place its own power to deny the executive withdrawal in the future. With this power comes the responsibility to be aware of when such power exists and to use it to scrutinise the executive if it wishes to withdraw. The executive’s position is also altered. It may think twice before initiating legislation that would set in place the unmaking principle. If it does, it may seek in advance parliament’s authorisation for future withdrawal, possibly in exchange for concessions.
The European Convention on Human Rights (ECHR) as a case study
One can demonstrate the possible impact of the unmaking principle by applying it to the European Convention on Human Rights (ECHR). It is unclear whether the current government will attempt to withdraw from it, but it remains a possibility, at least so long as there remains talk of a British Bill of Rights. According to the unmaking principle in Miller, if the executive wishes to withdraw from the ECHR, it must seek parliament’s approval first, if withdrawal would change UK domestic law in any way, or diminish rights of individuals.
We may therefore set up the following hypothetical future scenario. The executive wishes to withdraw from the ECHR without parliament’s approval, knowing that parliament may refuse. An individual, ‘C’, applies to the High Court for a declaration that ‘it would be unlawful for Her Majesty’s Government to withdraw the United Kingdom from the European Convention on Human Rights without an act of parliament authorising such withdrawal’. In proceedings, C may use Miller to argue that the executive does not have such power because withdrawal would change UK domestic law or diminish rights of individuals.
Before exploring some of C’s options, there is one point to address. It may appear a foregone conclusion that the UK’s withdrawal from the European Convention on Human Rights would diminish rights of UK citizens or, at least, change domestic law. However, this is not so. The EU treaties are far more intertwined with UK domestic law than the ECHR, having largely been incorporated directly into domestic law by the ECA. The ECHR has not been incorporated in this way. The closest law in the UK we have to incorporation of the ECHR is the Human Rights Act 1998 (HRA). The HRA is at least semi-independent of the ECHR, and certainly more so than the ECA is of the EU treaties. Therefore, it is more difficult for C to argue that withdrawal from the ECHR would change UK domestic law or diminish rights of individuals.
The following are just some of C’s options for arguing that withdrawal from the ECHR would alter UK domestic law or diminish rights of individuals, and therefore require parliament’s authority.
First, C may highlight that if the UK withdraws, UK citizens will lose the right to challenge their own government (this is called an ‘individual petition’) in the European Court of Human Rights (ECtHR), because the UK would no longer be a High Contracting Party under Article 34 of Protocol 11 to the ECHR. C would be relying on the second limb of the unmaking principle. One difficulty for C would be that this right of individual petition is not a ‘domestic’ right. It exists in international law, by virtue of the UK being a signatory to an international treaty. C would have to demonstrate that the second limb of the unmaking principle in Miller includes rights granted under international treaties alone, or demonstrate somehow that such a right is now part of UK domestic law.
Second, C may argue that if the UK withdraws, domestic law would be altered because the term, ‘Convention rights’, central to the HRA, would change in meaning. C would be relying on the first limb of the unmaking principle. The main remedies provided by the Act, under sections 3, 4 and 6, rely on a claimant proving that one of their ‘Convention rights’ has been violated. ‘Convention rights’ is defined in section 1 HRA as ‘the rights and fundamental freedoms set out in’ various Articles of the ECHR. The government may respond by saying that the ‘Convention rights’ would still exist after withdrawal; the only difference would be that this text would be sitting in a treaty to which the UK is no longer a party. However, C may respond that the content of these Convention rights would have changed. The Convention rights which apply to citizens in UK courts are a mixture of the Convention text, the jurisprudence of the ECtHR interpreting the text and any manipulation of this jurisprudence by UK courts as they apply it. Withdrawal from the ECHR would alter at least the first two ingredients in this mixture. First, the ‘Convention rights’ in the HRA would no longer be from a text which the UK may negotiate at an international level. Second, the ECtHR jurisprudence would change. One element of this jurisprudence is that it is developed in light of the common practice of High Contracting Parties. If the UK withdraws, its practices would not be taken into account. This is presumably one of the justifications for the ECtHR having a judge from each party state. It would not fit the judicial role for each judge to be representing their nation in a partisan fashion. Instead, the purpose of having a judge from the UK, for example, would be to add an understanding of its legal system and human rights practice. Using these two ingredients, C may establish that withdrawal from the ECHR would change domestic law by changing the meaning of ‘Convention rights’ in the HRA. The government may dispute that the second ingredient is actually an ingredient, by pointing to the fact that UK courts are only bound to take ECtHR jurisprudence ‘into account’, as per section 2 of the HRA. However, the House of Lords has effectively established this jurisprudence as a key part of the mixture, through the Ullah principle (R (Ullah) v Special Adjudicator  UKHL 26 ): that UK courts should, in the absence of special circumstances, follow any clear and constant jurisprudence of the ECtHR.
Third, C may argue that if the UK withdraws, domestic law would be altered because provisions in UK domestic law would be ‘deprived of any practical application’, using the terminology of Miller (). An example of such a provision would be the ‘power to take remedial action’ in subsection 10(2) HRA. This is the power for a Minister to change legislation by order. One of the ways this power is triggered is if it appears to the Minister that the legislation is incompatible with an obligation of the UK arising from the ECHR, having regard to a finding of the ECtHR in proceedings against the UK. If the UK withdrew from the EHCR, this provision would be deprived of practical application in at least two ways. First, there would be no obligations of the UK arising from the ECHR with which legislation may be incompatible. Second, there would be no finding of the ECtHR in proceedings against the UK to which the Minister may have regard. Furthermore, this provision is analogous to subsection 2(2) ECA. The court in Miller held that the power in subsection 2(2), to ‘make provision’ for the purpose of implementing any EU obligation, would be ‘deprived of any practical application’ because there would no longer be any EU obligations on which to base the exercise of the power (). This demonstrates the breadth of the unmaking principle. C need not show that the meaning of words used in domestic law would change. They must merely show that some provisions would be redundant or ineffective in the future.
Therefore, C would have a viable route to proving that parliament must authorise the UK withdrawing from the ECHR.
As aforementioned, this blog post has explored only one of many possible consequences of Miller. The others bear further examination. In the very near future, the most important development for the unmaking principle will be whether it survives the Supreme Court.
About the author
Harmish Mehta is a Research Volunteer at the Constitution Unit. He holds an LLB in Law from the London School of Economics.