I can understand the reaction that Miller is an example of ‘judicial activism’. The High Court did not adopt a narrow interpretation of earlier case law on the relationship between prerogative powers and legislation. Instead it interpreted earlier cases as establishing the ‘constitutional principle that unless Parliament legislates to the contrary, the Crown shall not have power to vary the law of the land by its exercise of prerogative powers.’ It interpreted the intention of Parliament broadly; the European Communities Act 1972, a ‘statute of special constitutional significance’, demonstrating an intention of ‘switching on the direct effect of EU law’. It deployed a more abstract analysis of the constitutional consequences; can the Crown use prerogative to trigger art. 50 given that this may lead to circumstances in which rights would be removed without future specific parliamentary authority. However, it is important to put the case in its constitutional context. This is not a judgment claiming power for the courts from the legislature. It does not overturn legislation. Nor is a judgment of such constitutional importance, where a declaratory order is sought and issues are raised in a preliminary, abstract manner, unsuited to an assessment of broad constitutional principles rather than a narrow interpretation of precedent. The judgment reinforces parliamentary sovereignty, recognises the constitutional reality of the UK’s membership of the EU and maintains the balance of power between all three institutions of the constitution. It recognises the important role of Parliament in protecting rights, ensuring there is full democratic debate and not erosion by the executive acting alone. It is the judiciary performing its role in preserving the principles of the UK constitution; balancing the ultimate sovereignty of Parliament with the rule of law. This is not ‘judicial activism’. It’s a judgment of constitutional principle written for a public audience.

Alison Young is Professor of Public Law at the University of Oxford and a Fellow of Hertford College.

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