As we wrote yesterday (see here) the hearing has now started of the High Court challenges to the Government’s position that it can trigger Article 50 by use of the royal prerogative and without the need for an Act of Parliament. Those challenges are based on domestic principles of constitutional law.
If you’re interested in seeing the detail of what happened on Day One of the hearing, the full transcript is now available here.
One point which seemed to exercise the Court in particular is whether it would be open to the UK, once an Article 50 notification has been given, to withdraw that notification. That is a question of EU, rather than domestic, law but has implications in the case in terms of the timing of any Parliamentary approval – would approval have to be in place before the Article 50 notification was given or could it come later? However, the answer to that legal question would undoubtedly also have implications in terms of the dynamics of the UK’s withdrawal negotiations with the EU 27 and in terms of the debate here in the UK as to the terms of withdrawal.