Judicial Review of Royal Prerogative and the Case of Prorogation: Process not Substance; Exception, not Rule.

This paper takes as its starting point Stephen Gardbaum’s much debated proposal of a revived political process theory to offer a fresh perspective on a key constitutional issue: the extent to which courts can impose some basic rule-of-law controls over the exercise of the prerogative powers of the British Crown, “inherited” also by Canada and New Zealand. It thus constitutes a case study on how far Gardbaum’s broad, global sketch of his theory can be successfully worked up into a ‘thick’, local model, by testing this British application against his critics. The article starts with the British prorogation case, Miller II, arguing that the decision, while bold and innovative, was sharply limited to a defense of constitutional process, as was Miller I, classic instances of the kind of procedural constitutional role suggested for the judiciary in Gardbaum's model. Both Miller decisions saw the courts police the democratic workings of the constitution, but neither concerned substantive policy issues. The paper then goes on to propose a recategorization of the whole corpus of UK case law on judicial review of royal prerogative. It argues that the cases can be divided into those that have sought to check a substantive government policy (overwhelmingly unsuccessful) and those process-based cases that have sought to protect and preserve the role of Parliament in the constitution (overwhelmingly successful). It contends that this finding sheds important new light on the overall question of how far Crown prerogative powers have been subject to basic rule-of-law controls, a subject on which it contends that the public law scholars have been much too sanguine.