UK constitution in Dicey waters?

The upheaval of 2016 could overshadow every constitutional change since the late 19th century, writes Stephen Tierney, professor of constitutional theory at Edinburgh University and legal adviser to the House of Lords Select Committee on the Constitution, in this year’s Scottish Legal News Annual Review.

Following the vote to leave the EU last June, the UK government and most commentators believed “the decision to trigger Article 50 notification was a discretionary matter for the Crown”.

However, all bets were off after the High Court ruling in Miller.

In the Annual Review, published by our sister publication Scottish Legal News, Professor Tierney explains: “The court accepted the applicants’ argument that the relevant prerogative power had been displaced by legislation, in particular the European Communities Act 1972 (ECA).”

Professor Tierney discerns three fundamental constitutional issues raised by the case: “the nature of parliamentary supremacy and its relationship to popular sovereignty as exercised through a referendum; the relationship between parliament and executive within the constitution; and the increasing entrenchment of devolution which seems to be moving the UK in a federal direction”.

Neither court saw the Brexit referendum as “constitutionally significant”. But Professor Tierney thinks the reasoning inconsistent: “For a judicial approach that otherwise sought to take an expansive methodology to constitutional interpretation, looking behind constitutional form to the political realities of constitutional substance, this is puzzling.”

The court, he adds, went from an “inventive approach” to a “narrow formalism” and, after invoking the doctrine of parliamentary supremacy, failed to describe the political sovereignty “that underpins it”.

Professor Tierney notes that the High Court quoted Dicey, who said that “the judges know nothing about any will of the people except insofar as that will is expressed by an act of Parliament” only to misread him by concluding that, as such, the referendum was constitutionally irrelevant.