Judges at the Court of Justice of the European Union (CJEU) will hear arguments next week on whether EU law would permit the UK to unilaterally revoke its notice to leave the EU under Article 50 of the Treaty on European Union.
On 3 October the Inner House referred the following question to the CJEU under the EU preliminary reference procedure, which empowers the CJEU to tell Member State courts how EU laws, including the EU treaties, should be interpreted:
Where, in accordance with article 50 of the Treaty on European Union, a Member State has notified the European Council of its intention to withdraw from the European Union, does EU law permit that notice to be revoked unilaterally by the notifying Member State; and, if so, subject to what conditions and with what effect relative to the member state remaining within the European Union?
The question was asked in the context of an action by a group of Scottish MPs, MEPs and MSPs from across the political spectrum, who want to know whether the UK could "cancel" Brexit if the Prime Minister's proposed deal was unsatisfactory.
The Inner House had earlier refused the UK Government permission to appeal to the Supreme Court against that decision to make the reference.
The Supreme Court has now refused a direct application on the grounds that (as we pointed out in our blog here) UK law does not allow an appeal against an interlocutory (i.e. non-final) decision reached unanimously by the Inner House. The Supreme Court did not appear to consider the EU law rules against appealing a decision to make a reference, probably because the UK law position settled the matter.
So what happens next?
As we noted in our blog on the original Inner House judgment, the Inner House decided to refer the question to the CJEU because it did not think it was purely hypothetical and academic. However, the CJEU can still refuse to answer the Inner House's question if it disagrees and concludes that it is academic.
The UK Government has published its submissions to the CJEU, which argue that the question is hypothetical since it has no intention of revoking the Article 50 notice. The politicians who have brought the case argue that Parliament could nevertheless legislate to require revocation, and need to know whether EU law would recognise that revocation.
The CJEU will hear both sides' arguments on 27 November, under its expedited procedure. It would normally take several months to then publish a decision, but it is expected that (if the CJEU decides to answer the Inner House's question) a ruling will be forthcoming before the UK Parliament has to vote on a final withdrawal agreement.
As is often the case with Brexit, it is difficult to predict what will happen next.