For the Government to win its appeal it needs to make clear that using the prerogative power to trigger Article 50 would not in any way flout parliamentary sovereignty. The argument before the Supreme Court today went some way towards this end.
Opening the case for the Government, the Attorney General Jeremy Wright argued that the Houses of Parliament had been and would remain involved in the Brexit process. Triggering Article 50 after a national referendum, facilitated by an Act of Parliament, was not at all executive action on a whim or in defiance of Parliament or statute.
One might add that the Government is responsible to the Houses and can be unseated if the Commons loses confidence in it.
Developing the Government’s submissions in detail, James Eadie QC, argued that the European Communities Act 1972 presupposed the exercise of the prerogative power to make and withdraw from treaties. Legislation after 1972 had restricted the prerogative in various specific ways but had never imposed limits on withdrawal from the European Union treaties.
Relying on Professor Timothy Endicott’s Policy Exchange lecture last week, he defended the prerogative against the charge that it was a relic of arbitrary, despotic government, arguing instead that it was both central to modern government and very well-established and constitutionally respectable.
The Government’s argument turns on the distinction between the international legal order, in which use of the prerogative makes and unmakes treaties, and the domestic legal order, which treaties cannot change unless Parliament legislates to this effect.
Eadie took the Supreme Court through the various ways in which Parliament has chosen to transpose international law into domestic law. The 1972 Act does so in a specific way, giving direct effect to the UK’s legal obligations under the EU treaties as they stand from time to time.
Some of the judges queried whether if the UK’s entry into the EEC (as it then was) had required the joint action of Parliament (enacting the 1972 Act) and the Government (ratifying the accession treaties) how it was that the Government could withdraw unilaterally.
Eadie’s answer was strong: entry into the treaties had been by way of the prerogative, with Parliament legislating to facilitate the domestic legal effect of these treaties, and withdrawal continued as ever to be a prerogative matter.
The question of scale seemed to bother some of the judges. That is, they asked whether there might not be a difference between using the prerogative to change the UK’s obligations under the EU treaties and withdrawing from those treaties altogether.
Much of the afternoon’s discussion concerned restrictions on prerogative action enacted by Parliament from 1978 onwards. Some of the judges, understandably enough, queried how this could bear on the meaning of the 1972 Act.
Eadie’s answer was not altogether satisfactory. He implied that its meaning was to be settled now, in view of the legislation enacted since, without ever quite explaining how these statutes intersect.
He did a reasonably good job at addressing the idea that the 1972 Act was a constitutional statute, but rather oddly introduced the idea that it was a statute that might be given a flexible, generous interpretation.
This may have been a misstep: much better if the Government had simply insisted that the Court follow the clear terms of the 1972 Act.
This article first appeared in the Daily Telegraph — click here to read it on the newspaper’s website