The UK Supreme Court on Tuesday will consider whether Prime Minister Boris Johnson acted unlawfully in advising the Queen to suspend, or “prorogue,” Parliament for more than a month.
Eleven justices sitting in London must decide between two competing rulings – one from Scotland’s highest civil court, and one from the high court in London, which has jurisdiction in England and Wales. They are also considering a third case from Northern Ireland.
There are two main issues at stake. The first is “justiciability” – a word that is likely to come up a lot. It simply means whether the court has the power to make a ruling on a particular issue.
The second is legality – whether the government’s decision in this case was legal or not. Boris Johnson, the UK Prime Minister, said the reason for suspending parliament was to restart the parliamentary session with a new legislative program. Opponents say the real reason was to limit the amount of time available for Parliament to prevent a no-deal Brexit by the deadline of October 31.
The decision to suspend Parliament was taken under the “royal prerogative.” This term relates to powers that can be exercised by the monarch without the consent of Parliament. In practice, the UK monarch acts on the advice of the Prime Minister.
By convention, these powers are regarded as inherently political in nature, and are therefore not subject to review by the courts.
The high court in London stuck rigidly to this convention. Three judges, including the Lord Chief Justice, did not even go on to considering the substance of the government’s decision.
The judges in Scotland took a different approach. They considered the legality of the decision in parallel with justiciability. They came to the conclusion that, even though the courts would not usually intervene in political matters, the government’s actions were so egregious in this case that the court was justified in making an exception.
The judges could go in one of three directions. They could accept the ruling of the high court in London entirely, sticking to UK legal convention. That would result in Parliament remaining suspended until October 14.
Or they could side with the Scottish court. In that case, the claimants in the case could go back to Edinburgh and apply for a court order to force the immediate reopening of parliament.
There is a third way – the justices could agree with the Scottish court that decisions taken under prerogative powers can be reviewed by the courts, but only in limited circumstances. They could also decide that in this instance, the government acted legally.
The Supreme Court has set aside three days for legal debate and argument. The earliest the judges could give their decision, therefore, would be Thursday afternoon. It seems much more likely that a ruling would come on Friday or even early next week, given the complexity of the arguments and importance of the decision.