Kenneth Campbell: Constitutional Dogs That Barked and Dogs That Did Not: The Scottish Continuity Bill in the Supreme Court


Somewhat overshadowed by the Wightman saga, and the unscheduled Conservative leadership demarche, the UKSC decision in the UK Withdrawal from the European Union (Legal Continuity)(Scotland) Bill compatibility reference was handed down in the same week in December. It will be argued this decision contains more of lasting constitutional significance which lies both  in the court’s approach to Parliamentary sovereignty, and in the likely consequences for the territorial constitution/devolution settlement in the aftermath of Brexit.

In its basic intent, the UK Withdrawal from the European Union (Legal Continuity)(Scotland) Bill (“the Continuity Bill”) occupies some of the same ground as the European Union (Withdrawal) Act 2018, though both were bills at time the battle was joined. It will be recalled that at the time of publication of the European Union (Withdrawal) Bill (“the Withdrawal Bill”), the Scottish and Welsh governments took a common position against the provisions so far as relating to reallocation of EU powers falling within devolved competence. Politically that was striking, given the Welsh administration comprises a Unionist party in a nation which voted to leave the EU, while the Scottish Government is conducted by an avowedly pro-independence party in a nation which voted by a substantial margin to remain. In that respect it is best viewed as a demonstration of solidarity in defence of the devolved institutions, and perhaps reflective of the different sense of their importance at the centre and in the devolved nations.

The broad sweep of the Supreme Court’s decision has been surveyed by Aileen McHarg and Chris McCorkindale on this blog, and by Mark Elliott elsewhere, and this post seeks to explore further several elements of the decision, particularly about institutional relations and parliamentary sovereignty.

Status of the Scottish Parliament

In light of the court’s subsequent discussion of what appears to be a multifaceted version of the legislative supremacy of the UK Parliament, it is of note that the Court’s analysis begins with an encapsulation of the character of the Scottish Parliament which is worth quoting at length:

The powers of the Scottish Parliament, like those of Parliaments in many other constitutional democracies, are delimited by law. The Scottish Parliament is a democratically elected legislature with a mandate to make laws for people in Scotland. It has plenary powers within the limits of its legislative competence. But it does not enjoy the sovereignty of the Crown in Parliament; rules delimiting its legislative competence are found in section 29 of and Schedules 4 and 5 to the Scotland Act, to which the courts must give effect. And the UK Parliament also has power to make laws for Scotland, a power which the legislation of the Scottish Parliament cannot affect: section 28(7) of the Scotland Act. The Scotland Act must be interpreted in the same way as any other statute. The courts have regard to its aim to achieve a constitutional settlement and therefore recognise the importance of giving a consistent and predictable interpretation of the Scotland Act so that the Scottish Parliament has a coherent, stable and workable system within which to exercise its legislative power. This is achieved by interpreting the rules as to competence in the Scotland Act according to the ordinary meaning of the words used. [para 12]

These observations are of note because they serve as a reminder of the plenary nature of the legislative power of the Scottish Parliament, and, echoing the court’s decision in AXA, repeat the importance of its democratic mandate (cf. AXA para 46). Likewise the reader is reminded of the existence of limits on that competence prescribed by law are characteristic of the devolution scheme, and also of constitutional orders not characterised by parliamentary sovereignty. In other words, an implicit normalisation of both the political legitimacy of legislative action by the Scottish Parliament, and of locating its competence within legal constitutionalism. That perhaps also provides context for the court having little difficulty in dismissing the rather surprising frontal attack by UK law officers on the Continuity Bill as whole on the basis of its being “contrary to the constitutional framework underpinning the devolution settlement” [para 23]. In that respect, it is noteworthy (and welcome) that the court took care to confirm that section 33 of the Scotland Act provides exhaustive grounds/bases for assessing legislative competence in references of this kind (see para 26).

Intergovernmental relations

It is now trite to notice that the arrangements for intergovernmental relations are the most opaque part of devolution within the UK. While the Northern Ireland Act does contain some provisions about this, these are largely directed to the north-south axis, rather than the east-west axis. By contrast, there is little formal provision in the Scots or Welsh schemes.

Of course the practical lubricant for minimising many boundary problems is the Sewel convention, in terms of which the UK Parliament will not normally legislate on a devolved matter without the consent of the Scottish Parliament (cf. Scotland Act s 28(8)). As the court notes, under reference to Lord Hope’s judgment in Imperial Tobacco v Lord Advocate [2012] UKSC 61:

disputes between the Scottish Parliament and the UK Parliament as to legislative competence have been avoided, partly by the use of legislative consent motions passed by the Scottish Parliament and partly by the care which officials within the Scottish Parliament have taken to ensure that measures which the Scottish Parliament passes are within competence [para 20]

In its written argument in Miller v Secretary of State for Exiting the EU [2017] UKSC 5, the Scottish Government set out a table of legislative consent motions since the inception of the Scottish Parliament, and at the point when that case was argued in December 2016, there were 164 items listed. From this the operational importance of the convention can be clearly seen.

In May 2018, the Scottish Parliament voted 93-30 to withhold consent to the Withdrawal Bill. As is well known, the UK Government’s decision to press on with the bill was the first occasion on which legislation has been passed in the face of such a refusal of consent, and thus a politically significant moment. It might reasonably have been expected that the convention would feature in this case, for forensic reasons as much as any other. Against all of that background, it is interesting to note that the court simply referred to the convention, and affirmed its treatment of the topic in Miller (see paras 18 & 19). Contributors to this blog including Joe Atkinson, Paul Reid, and myself have commented on various conundrums to which the court’s treatment of the Sewel convention in Miller gives rise, so that, on one view, an opportunity for more extended exploration of the issues surrounding the convention and its statutory expression was passed up. Of course, the convention was not as central an issue as it was in Miller, at least in its Northern Ireland expression, and the court’s approach can be explained on that basis.

Politically, of course, legislating in the absence of consent has been extremely controversial. On one view, that is the convention operating as intended. In other words, the intent of sections 28(7) and 28(8) of the Scotland Act is to preserve the power of the UK Parliament to legislate in relation to devolved matters, but with an attendant political cost where legislative consent is withheld by the Scottish Parliament. That is an affirmation of the political constitution in operation. It might also be argued the the extended discussions at both official and ministerial level between the UK and devolved governments about the shape and operation of the Withdrawal Bill is also an instance of the Sewel convention in operation, and in particular the important changes made to what are now sections 11 and 12 and schedule 2 to the European Union (Withdrawal) Act. As is evident from Miller and Imperial Tobacco, such discussions are routinely used to establish a via media between the devolved and central executive institutions, and those discussions have continued even while the final shape of the Withdrawal Bill was being debated in the UK Parliament and beyond. Eventually, the Welsh Ministers came to be satisfied about the amended shape of the bill, so that consent was forthcoming. In that sense, the convention has operated as intended.

On the other hand, it might equally be said that the sequence of events points sharply to the limitations, if not outright gaps, in the institutional architecture. Section 28(8) was added to the Scotland Act as a result of the Smith Commission following the 2014 Scottish independence referendum. Post Miller, we know that it has no justiciable character, but its political valence is now unclear. That remains a constitutional conundrum which will require to be resolved, and the more so because of the position adopted by the UK law officers in argument in both Miller and the Continuity Bill reference that the Sewel convention is an executive convenience, rather than a matter of legislative comity essential to the notion of devolution.

Of course, it might also be thought that the circumstances of this particular exercise of legislative power by the UK Parliament was not foreseen at the time of devolution, and that the nature of the issues arising in the wake of the Withdrawal Bill were (and are) so fundamental, that a more exacting threshold ought to apply. However, despite the undoubted effect of the European Union (Withdrawal) Act on the structure of devolution, there is nothing in the language of section 28 of the Scotland Act to mandate the notion of such a higher standard, nor, it seems, was that the focus of parties’ argument before the Supreme Court.

Parliamentary supremacy/sovereignty

If the Sewel convention was the dog which barked faintly, if at all, in the court’s judgment, the legislative supremacy of the UK Parliament was the dog which barked loudly, if not always distinctly.

Here it is necessary first to set the context. Section 17 of the Continuity Bill contained a requirement for consent of the Scottish Ministers to UK subordinate legislation containing a “devolved provision”  which modifies or otherwise affects the operation of –

(i) retained (devolved) EU law, or

(ii) anything that would be, on or after exit day, retained (devolved) EU law.

For this purpose, a ‘devolved provision’ means a “provision that would be, if it were contained in an Act of the Scottish Parliament, within the legislative competence of the Scottish Parliament.” In other words, the Scottish Ministers’ consent would be an essential step for the effectiveness of such UK subordinate legislation, at least in its application to Scotland.

Section 17 was the only provision which the court found to be outwith the legislative competence of the Scottish Parliament from the outset. As other commentators have noted, in its discussion of this, the court has seemed to face in several directions on the effect of parliamentary legislative supremacy – expressed as “parliamentary sovereignty” (see paragraph 41).  Paragraph 52 contains the key conclusion: the court there held that law-making by the UK Parliament which was dependent on consent of Scottish Ministers “would be inconsistent with the recognition by section 28(7) of the Scotland Act of its [the UK Parliament’s] unqualified legislative power” – including in relation to matters which are devolved. This was on the basis that the substantive effect was to limit an aspect of the UK Parliament’s capacity to legislate for Scotland, by including the conditionality of Scottish Ministers’ consent. For that reason, section 17 was outwith the legislative competence of the Scottish Parliament.

It might be thought, that was simply a reaffirmation of parliamentary legislative supremacy, but the court went on to hold in terms that section 17 did not impinge on the sovereignty of Parliament [para 63]. That was on the basis that the section did not purport to alter “the fundamental constitutional principle that the Crown in Parliament is the ultimate source of of legal authority nor would it have that effect” [para 63 emphasis added]. Now it is true that this observation was made in the context of a different part of the UK law officers’ argument, namely whether section 17 impinged on the fact that the UK Parliament is a reserved matter under the devolution scheme, that is, the devolved legislature may not legislate about it. Mike Gordon has suggested the court’s reasoning in these passages can be reconciled only if a ‘manner and form’ understanding of parliamentary supremacy is implicit in the court’s approach. He suggests that implicit in paragraph 64 is a conclusion that “legislative consent conditions aren’t per se incompatible with parliamentary sovereignty”, but that the formulation of section 28 of the Scotland Act precludes this in legislation of the Scottish Parliament.

While that is a plausible reading, it is also possible that the court is taking a step towards articulating a broader conception of parliamentary sovereignty consistent with modern constitutional practice. The notion of ‘parliamentary sovereignty’ is frequently invoked without elaboration in legal as well as political discourse, something Gordon acknowledges in Parliamentary Sovereignty in the UK Constitution (preface & Ch 1). It is also a feature of Supreme Court case-law over the last several years that fundamental constitutional rights and principles have been reassessed through the prism of the common law, rather than Convention or EU law, for example AXA v Lord Advocate [2011] UKSC 46, HS2 Action Alliance v Sec of State for Transport [2014] UKSC 3, Kennedy v Charity Commissioners [2014] UKSC 20, and Pham v SSHD [2015] UKSC 19. Until now, the court has perhaps not had to explore in detail what we mean by ‘parliamentary sovereignty’ in the current age, and it may be that the building blocks for doing so are in the process of being fashioned. Thus we have a statement about the normative order in paragraph 63, and an attempt to fashion a more limited, statute-based operationalisation in paragraph 52.

Perhaps there is a broader reconceptualisation too, since another dimension which requires further elaboration is the full consequence of calling into existence of concurrent legislative competence in the devolved legislatures. It may be that that does not affect the normative dimension of the UK Parliament as the ultimate source of legal authority, but some practical operational boundary is another matter. Further, the circumstances in which the Sewel convention came to be enacted into the Scotland Act in the aftermath of the 2014 referendum are significant politically, if not (in light of Miller) legally. It is perhaps understandable that the court was not keen to revisit the convention question relatively soon after Miller. Nonetheless, it is possible to discern amidst the noise features which might be developed in future consideration of parliamentary supremacy/sovereignty. After all, in R (Jackson) v Attorney General [2005] UKHL 56, Lords Hope and Steyn expressed doubts about whether parliamentary sovereignty was beyond judicial scrutiny in all circumstances. That was, of course, not the view of the whole court, and has been the subject of subsequent critique (including by members of the same court); nonetheless, that two members of the most senior court felt able to offer that view is significant, and key elements of the constitution have evolved further since that landmark decision.


During oral argument in the Continuity Bill case, the Lord Advocate submitted that in the event of the UK’s exit from the European Union it would not (as appeared to be the UK Government’s position in argument) be a matter of returning to the constitution of 1972 or even of 1998. In this he was surely correct: the  constitution has evolved significantly on a number of levels, not least in consequence of devolution. As the Commons Public Administration and Constitutional Affairs Committee made clear in its report Devolution and Exiting the EU: reconciling differences and building strong relationships (2018) HC1485, the full significance of the development of a territorial constitution is thrown into sharp relief by the exit process. The decision of the UK Supreme Court in the Continuity Bill case adds disappointingly little to the intergovernmental relations dimension, but seems to open up questions about what parliamentary sovereignty, or legislative supremacy, might mean in the contemporary constitutional ‘settlement’.

Kenneth Campbell QC is an Advocate at Arnot Manderson Advocates, Edinburgh, a Barrister at Lamb Building, London and doctoral researcher at Edinburgh University Law School.

(Suggested citation: K. Campbell, ‘Constitutional Dogs That Barked and Dogs That Did Not: The Scottish Continuity Bill in the Supreme Court’, U.K. Const. L. Blog (14th Jan. 2019) (available at