The Accommodation of Parliamentary Sovereignty in the UK’s Territorial Constitution

Abstract

This thesis asks whether, and if so, how parliamentary sovereignty can be satisfactorily accommodated in the UK’s territorial constitution. This question means considering whether parliamentary sovereignty - a, if not the, central principle in the UK’s constitution - can coexist intellectually coherently with the UK’s contemporary devolution settlement in a way that accurately and meaningfully characterises both relevant phenomena. In other words, it considers whether the UK’s territorial constitution can be considered consistent with parliamentary sovereignty, and what the implications of achieving that consistency are for devolution. It argues that parliamentary sovereignty can be accommodated in the UK’s territorial constitution in a way that properly and fully reflects parliamentary sovereignty’s nature and its doctrinal treatment, and which does not necessarily undermine devolution or have centralising implications. The accommodation question is posed in light of some important contextual issues, three of which are illustrative: First, a growing trend of centralisation in the UK, wherein the devolved institutions are having their powers reduced (at least in de facto terms) and devolution is being perceptibly narrowly construed by the courts. Second, the traction exerted by a broader, more brittle account of parliamentary sovereignty, both in the courts and in political discourse. Third, the instrumentalization of the normative purchase of ‘sovereignty’ generally, and parliamentary sovereignty specifically, to justify or necessitate the recentralisation of constitutional power. The dominance of the sovereignty principle, this thesis argues, serves to some extent to determine what kind of territorial constitution is possible in the UK. It is therefore important to consider whether, and how, the current devolution framework can be meaningfully said to be consistent with parliamentary sovereignty, or whether that consistency can only be achieved in a way that undermines, or fails to properly reflect the fundamental character of, devolution. The thesis presents two models that might potentially achieve this ‘accommodation’. One - described as the ‘reconciliatory approach’ - recognises the flexibility of the sovereignty principle and argues that this enables sovereignty to be reconciled with a full recognition of the core components of devolution. The second model - described as the ‘protective approach’ - considers parliamentary sovereignty as a much broader, more brittle and dominant constitutional force, thus implying a far narrower construction of devolution. The thesis unpacks each of these approaches as categories of practices, that is, legal mechanisms and theoretical frameworks, primarily sourced in case law, academic work, and legislation. Each approach differs on what it considers necessary to provide an account of the territorial constitution which reflects what it identifies as the important aspects of the sovereignty principle. This thesis argues that the former - the reconciliatory approach - is preferable, and that only it can provide ‘satisfactory’ accommodation. That approach provides a means to intellectually reconcile both phenomena in a way that accurately characterises parliamentary sovereignty, consistent with that principle’s contemporary doctrinal treatment, and does so without necessitating the recentralisation of constitutional power in a way that undermines, or fails to recognise the fundamental character of, the devolution settlement. The protective approach, by contrast, fails to coherently reflect parliamentary sovereignty and cannot accurately account for some of the key aspects of the devolution settlement. The thesis argues that parliamentary sovereignty does not inevitably lead to centralisation, but the protective approach - which does - can be opposed on the basis of its inaccuracy as an account of the constitution.