Judicial Review of Legislation in the UK: Fundamental Common Law Principles as "Constitutional Principles" Limiting the Sovereignty of Parliament?

The aim of this paper is to explore the role of judicial review of legislation in the UK from a legal constitutionalist’s point of view. After having introduced the reader to the origins of judicial review of legislation in general and the two theoretical models of constitutionalism, the UK’s system of constitutionalism will be analysed in particular. In this context, the process of “juridification” and “judicalisation” will be discussed in order to show that the British doctrine of Parliamentary sovereignty - famously articulated by Dicey in 1885 - is currently under attack. The main focus of this research paper is on the theory of common law constitutionalism (CLC theory), according to which the common law is seen as constituting a higher order of law, a moral ideal and a superior form of public reason, and therefore the ultimate controlling factor of Parliament’s actions. On the basis of the academic theory, the judicial reception of this theory will be analysed with particular attention to the House of Lords’ decision in Jackson in 2005. It will be argued that the system of the common law constitutionalism in the UK is not very different from the system of legal constitutionalism: Firstly, fundamental principles embedded in the common law like the rule of law are similar to constitutional principles of codified supreme constitutions, providing for benchmarks of judicial review of legislation. Secondly, the requirement of exceptional circumstances for invalidating legislation in the CLC system corresponds to the idea of (strong) judicial self-restraint in legal constitutionalist systems.