Supreme Court rules Theresa May CANNOT trigger Article 50 without parliamentary approval

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By Katie King on

Most important constitutional law case of a generation concludes with an unexpected split decision


The Supreme Court has ruled that Article 50 cannot be triggered by prerogative power alone, meaning parliament must vote on whether to begin our withdrawal from the European Union.

Clearly swayed by lead claimant Gina Miller — and her counsel Lord Pannick QC’s enviable advocacy skills — the highest court in the land decided this morning that it would be unlawful to deny MPs a free vote.

Legal Cheek has been informed that government lawyers were given a copy of the judgment at 8am on the Supreme Court’s premises. At 9.15am, the Prime Minister and Miller were told about the decision by their counsel.

It was just 15 minutes after this — and feet away from some pretty bizarre outside court shenanigans — that Lord Neuberger shared the decision with the rest of the world.

Reading out a summary of the judgment to a packed Courtroom 1, the president of the court reminded spectators that this judicial review had “nothing to do” with whether the United Kingdom should exit the EU.

The main issue at hand was whether the government can trigger Article 50 without parliamentary approval; the answer to this is no. The reason is that withdrawal from the EU means a withdrawal from EU treaties, which will alter UK citizens’ rights. Any change to citizens’ rights must be made in the only way permitted by the constitution, and that’s by an act of parliament. The court duly dismissed the government’s appeal.


However, it was a split decision: Lord Reed, Lord Carnwath and Lord Hughes dissented. The trio said that the effect of EU law under domestic legislation is inherently conditional on the application of EU treaties and our membership. Interestingly Lord Sumption, who is generally believed to be most ‘most Brexit-y’ of all the justices, went with the majority.

How the judges ruled:


On the devolution issues, there was not such a split. The court unanimously concluded that relations between the UK and the EU are reserved for the UK government/parliament and not for the devolved nations.

Though Brexiteers may be bummed out by the decision, they should take comfort in the following extract from the judgment:

What form [the required legislation] should take is entirely a matter for parliament. But, in the light of a point made in oral argument, it is right to add that the fact that parliament may decide to content itself with a very brief statute is nothing to the point. There is no equivalence between the constitutional importance of a statute, or any other document, and its length or complexity.

Speaking outside the iconic Westminster building this morning, Miller took the opportunity to thank her legal team at Mishcon de Reya and her Blackstone Chambers barrister Pannick “for conducting themselves with such integrity and thoughtfulness in the face of extraordinary and unwarranted criticism”. She “wholeheartedly” thanked those who had supported her throughout the challenge, continuing:

They have truly helped to bolster me in this most arduous process.

Indeed, whether you agree or disagree with the ruling, what’s undeniable is that it has been a real rollercoaster ride getting here.

The whole case has been mired in controversy from day one, with anti-EU protesters setting the tone early on by picketing law firm Mishcon de Reya.

After the first instance judgment was laid down by the High Court, right-wing media lost the plot when it went Miller’s way. The judges were described as “enemies of the people”, prompting fierce condemnation from the profession, but barely a murmur from appointed judiciary-defender Lord Chancellor Liz Truss.

The controversy picked up pace when the government launched its appeal.

There was that row about bias on the judges’ bench, after Lord Neuberger’s wife made some pro-EU tweets and Lady Hale made some controversial comments in Kuala Lumpur (the ones that really pissed off Iain Duncan Smith MP).

Miller herself has been dragged into the furore herself: bombarded with death and rape threats, a man was even arrested for sending her online racist abuse while the Supreme Court hearing was going ahead.

Against this, frankly mental, backdrop, there have been some lighter moments.

There was fascination with Lord Sumption’s ties and Lady Hale’s brooches. Barrister Rupert Myer’s spoof Twitter case commentary had us in stitches. There was the University of East Anglia professor who counted every word spoken by the Supreme Court to try to guess the outcome. Two of the case’s barristers were embroiled in a sweary Twitter spat, while the world became so comforted by Pannick’s soothing voice a new clothing line with the barrister’s face on it hit the market.

As for next steps, parliament is expected to vote on triggering Article 50 ASAP to keep as closely to May’s ‘I will start the withdrawal process by March’ promise. Though parliament is expected to vote in line with the referendum result, if the past few months have taught us anything it’s to expect the unexpected.

Read the judgment in full below:

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