By Mark Elliott
Professor of Public Law, University of Cambridge
This case arose when the Queen was advised by the UK Government to ‘prorogue’ Parliament. Proroguing Parliament means suspending it. This usually happens each year, bringing the existing parliamentary ‘session’ to an end and paving the way for the Queen’s Speech — in which the Government’s legislative plans are set out — and the start of a new session. Prorogation normally lasts only for a few days.
But in autumn 2019, the Government sought to prorogue Parliament for five weeks. This was at a crucial point in the Brexit process when parliamentarians were attempting (ultimately successfully) to legislate to require the Government to seek an extension to the Brexit process in order to reduce the likelihood of a ‘no-deal Brexit’.
The claimant argued that the attempt to prorogue Parliament for this duration was unlawful in the circumstances. The Government disagreed and further argued that the issue was ‘non-justiciable’, meaning that it was, in the Government’s view, not a question on which the Court could properly adjudicate.
The Supreme Court held that the matter was justiciable: while the case had arisen in acutely controversial political circumstances, the question before the Court was a legal question. In particular, said the Court, the central issue concerned the extent, or scope, of the prerogative power of prorogation.
This was a classically legal issue that could be properly addressed by the Court notwithstanding any surrounding political controversy. In determining the extent of the power, the Court took special account of two pertinent constitutional principles: parliamentary sovereignty and executive accountability to Parliament.
The Court concluded that the longer the period for which Parliament is prorogued, the greater the risk that those principles are compromised. It held that unless there is reasonable justification, prorogation will be unlawful if it frustrates or prevents Parliament from carrying out its constitutional functions. The Court considered that no reasonable justification had been provided and that the prorogation in question was unlawful.
Why, then, is this a controversial case? As with Miller I, part of the explanation lies in the political controversy surrounding the case. In relation to Miller I, for all that such controversy undoubtedly existed, it is clear that the Court confined itself to legal questions that could be severed from any related political matters.
Can the same be said of Miller II? The Supreme Court certainly thought so: it held that concerns regarding justiciability simply did not arise because the Court confined itself to an obviously legal question about the scope of a legal power.
However, critics argue that this involved considerable sleight of hand. In particular, they contend that the Court took a question about the adequacy of the Government’s justification — a question that, it is said by some, is really about the exercise of the power and which therefore does raise concerns about justiciability — and sought to pass it off as a purely legal question about the power’s extent.
Whether we find this critique persuasive may depend, among other things, on our broader views about the proper scope of judicial control more generally and about the extent to, and the way in, which fundamental constitutional principles serve to limit the exercise of governmental powers.