R (Miller) v The Prime Minister and Cherry v Advocate General for Scotland (2019) UKSC 41, commonly referred to as Miller II or Miller/Cherry, were joint landmark constitutional law cases on the limits of the power of royal prerogative used by the Government to prorogue the Parliament.
R (Miller) v The Prime Minister (2019)
In August 2019, Prime Minister Boris Johnson advised Queen Elizabeth II to prorogue (suspend) the UK Parliament for five weeks leading up to the Brexit deadline on October 31, 2019. The Prime Minister argued that this was a routine and lawful prorogation to prepare for a new parliamentary session. However, critics, including Gina Miller, a businesswoman and anti-Brexit campaigner, argued that the real purpose of proroguing Parliament was to limit its ability to scrutinise the government's Brexit plans or to prevent it from interfering with a no-deal Brexit.
The case was brought to the UK Supreme Court, which issued a unanimous judgment on September 24, 2019. The court ruled that the prorogation of Parliament was unlawful because it had an extreme effect upon the fundamentals of democracy, and the Prime Minister's advice to the Queen was unlawful, void, and of no effect. Parliament was therefore not prorogued, and it was for Parliament to decide when it should sit again. This decision was seen as a significant legal and political development in the ongoing Brexit process.
Cherry v Advocate General for Scotland (2019)
The Cherry case, often considered alongside the Miller case, was a related legal challenge in Scotland. A group of parliamentarians led by Joanna Cherry, a Member of Parliament from the Scottish National Party, challenged the prorogation of Parliament in the Scottish courts. The Court of Session in Scotland ruled that the prorogation was unlawful because it had the effect of frustrating or preventing the ability of Parliament to carry out its constitutional functions without reasonable justification.
The case was also appealed to the UK Supreme Court, and the Supreme Court issued its unanimous judgment on the same day as the Miller case. The Supreme Court upheld the ruling of the Court of Session in Scotland, concluding that the Prime Minister's advice to the Queen was unlawful, void, and of no effect. This decision aligned with the ruling in the Miller case and contributed to the broader legal and political discussions surrounding the prorogation of Parliament and its impact on the Brexit process.
These cases were significant because they clarified the limits on the Prime Minister's authority to prorogue Parliament and reaffirmed the principle that parliamentary sovereignty is a fundamental aspect of the UK's constitutional framework. The rulings were seen as a check on executive power and had a profound impact on the Brexit process and UK politics at the time.
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