The judgment from 11 justices on the UK’s highest court follows an emergency three-day hearing last week that exposed fundamental legal differences over interpreting the country’s unwritten constitution.
The decision was read out by Lady Hale, the president of the supreme court. Unusually, none of the parties were provided with advance copies of the judgment due to its extreme sensitivity.
Only seven of the 11 justices who heard the case were present in court.The first legal question the judges had to resolve was whether the prime minister’s decision – exploiting residual, royal prerogative powers – was “justiciable” and could consequently be subjected to scrutiny by the courts.
The English high court declined to intervene; the Scottish appeal court concluded that judges did have legal authority to act.In a unanimous verdict, the court ruled that Johnson’s decision to prorogue parliament can be examined by judges, overturning the ruling of the high court in London.
The court stopped short of declaring that the advice given by Johnson to the Queen was improper.
It was a question they did not need to address since they had already found that the effect of the prorogation was itself unlawful.
While speculation ahead of the ruling was that the court would find against the prime minister, the fact that the decision is unanimous came as a surprise. Most commentators had anticipated a split decision, as there was in the article 50 judgment in 2017.