Is the UK Supreme Court rogue to un-prorogue Parliament?

Abstract

On 24 September 2019, in a unanimous judgment the UK Supreme Court ([2019] UKSC 41) ruled that the Prime Minister’s action to prorogue (suspend) Parliament for 5 weeks in the run-up to the 31-10-2019 deadline of the UK leaving the European Union, was unlawful and of no effect, as it prevented Parliament from carrying out its constitutional functions without reasonable justification. Although the Court did not pronounce on the merits and demerits of Brexit, its decision delighted “Remainers” but appalled “Leavers”. The Court ruling epitomises the potency of constitutional review by an independent judiciary. The paper applies collective choice theory to analyse the ruling of the Supreme Court. This is accomplished by (a) examining the legal basis of the Court ruling; (b) reviewing arguments for judicial review and (c) exploring the effect of the Court as an additional player in the game of collective choice in a spatial decision model.