The unconstitutionality of the UK’s Supreme Court’s prorogation judgment

John Finnis has penned a devastating legal review.

Executive summary:

The Supreme Court’s judgment in Miller/Cherry [2019] UKSC 41 holds that Parliamentary sovereignty needs to be judicially protected against the power of the Government to prorogue Parliament.  But the Judgment itself undercuts the genuine sovereignty of Parliament by evading a statutory prohibition – art. 9 of the Bill of Rights 1689 – on judicial questioning of proceedings in Parliament. 

The Judgment was wholly unjustified by law. What it protects is not the sovereignty of Parliament, properly so called, but the practical opportunities of each House to pass Bills and scrutinise the Government – all redescribed as the “principle of Parliamentary accountability”. Those constitutionally vital opportunities, and that principle, have been protected for over 300 years, without significant mishap, by constitutional conventions which are policed politically, ultimately by the electorate. In working with the principles of Parliamentary sovereignty and political accountability, our constitutional law has always (partly under the influence of art. 9) distinguished firmly between legal rules (justiciable) and conventions (non-justiciable). The Judgment offers no plausible reason for transferring the conventions about prorogation into the domain of justiciable law.

The reason it does offer for this transformation is that, in some “extreme hypothetical” circumstance, the power to prorogue might be used to frustrate Parliamentary scrutiny of the Government (and what the Judgment miscalls Parliamentary sovereignty). The longstanding constraints on such abuse, in the form of conventions, strict legal preconditions for expenditure on maintaining government, and accountability to the electorate at legally defined intervals, constraints regarded as sufficient for hundreds of years, are suddenly assessed to be “scant reassurance.”  In its content (as distinct from its law-creating effect) that assessment of risks is neither legal nor constitutional, but purely political.   

Thus the Court suddenly assumes supreme responsibility for the maintenance and preservation of the pivot of the constitutional-political order.  It does so without mentioning that it is replacing some main elements of a constitutional settlement that has given effect, for hundreds of years, to certain tried and tested political assessments and judgments. Those were political judgments squarely concerned with what is constitutionally necessary and sufficient to forestall and counteract abuse in the Crown’s relationship to the Houses of Parliament and to the electorate.

In relation to the operation of its newly self-bestowed power, the Court says that it involves no more than defining the “boundaries” of the proroguing power, as distinct from taking over its “mode of exercise”. But the “legal standard” the Judgment invents to define those newly-legal boundaries is immediately deployed to review the mode of exercise. The Judgment collapses the distinction on which it relies. 

The Court’s misconceived review, in turn, fails to apply the “standard’s” main criterion, which looks to the effects of prorogation. The Judgment undertakes no serious review of effects. That would have shown that the impugned prorogation threatened nothing that Parliament could not rectify before the actual prorogation. Instead the Judgment faults the Government for providing no documented and, for the judges, sufficient reason for selecting “five weeks” rather than some lesser period which is not specified by the Judgment.

The Supreme Court’s review of the decision to prorogue ignores most of the immediately relevant statutory and political constraints and contextualising factors, and illustrates the ineptitude of judicial forays into high politics.  The likelihood that courts will be inept in venturing into the political realm is only one of the grounds for the historic rules of our law that the Judgment defies or rescinds, rules which clearly forbad judicial involvement in questions of high politics and preserved the distinction between conventions and law.

The Judgment should be recognised as a historic mistake, not a victory for fundamental principle. The next Parliament should exercise its authentic law-making sovereignty to reverse the Judgment’s misuse of judicial power. But legislation on prorogation, or on the relations of Crown and Parliament more generally, can do little to undo the damage done to our constitutional doctrine and settlement.