Decision to increase number of judges from nine to 11 shows significance of hearing

Eleven supreme court justices will hear the politically charged claim that Boris Johnson acted unlawfully in advising the Queen to suspend parliament for five weeks in order to stifle debate over the Brexit crisis.

All but one of the judges on the UK’s highest court will be on the bench on Tuesday when the case opens. The hearing will be livestreamed on the supreme court website.

A decision last Friday to increase the number of judges from nine to 11 signifies its constitutional significance and may indicate how finely balanced the arguments are considered to be.

Q&A What is the UK supreme court and how does it work? Show Hide The supreme court of the United Kingdom was formally established on 1 October 2009. It is the ultimate court for hearing cases of the greatest public or constitutional importance, and is the final court of appeal in the UK, except for criminal cases heard in Scotland. The supreme court took over the judicial functions of the House of Lords, separating the judiciary from the legislature. It brought an end to the system of appealing to the "lords of appeal in ordinary" - commonly known as the law lords. The court comprises the president and deputy president and 10 other judges of the supreme court. Judges are appointed by the Queen on the advice of the prime minister, to whom a name is recommended by a special selection commission. The prime minister is obliged to recommend this name. The judgments in all decided cases from the court are published on the court's website.

It is the first time the supreme court has been summoned for an emergency hearing outside legal term-time and only the second occasion for such judicial mass mobilisation – a similar number of judges sat in 2016 for the article 50 case.

Lady Hale, the first female president of the court who retires next January, will preside. Her deputy, Lord Reed, a Scottish judge, will succeed her in the new year. The only member of the 12-judge court not sitting will be Lord Briggs, a commercial law expert; the bench must have an odd number to prevent being deadlocked in a draw.

One of the many difficulties the justices face is how to reconcile differences between English, Scottish and Northern Ireland laws in the context of similar challenges against the prime minister’s proroguing of parliament. The London high court unanimously dismissed the prorogation claim while the Scottish appeal court unanimously allowed the challenge.

Three days have been allocated for legal argument and judgment could well be reserved. Due to the complexity of the hearings, the government will be represented by several QCs, among whom are Sir James Eadie, the “Treasury devil”, who appears for ministers in major litigation battles, and Lord Keen of Elie, the advocate general for Scotland and Ministry of Justice spokesperson in the Lords. Eadie will lead on the English cases, Keen on the Scottish.

Play Video 1:15 Boris Johnson says claims that he lied to the Queen are 'absolutely not' true - video

The prime minister told the BBC he had the “greatest respect for the judiciary”. Asked if he would recall Parliament if that’s what the supreme court said he ought to do, Johnson said: “I think the best thing I could do is wait and see what the judges say.”

A Northern Ireland prorogation claim, argued on behalf of Raymond McCord, a victims’ rights campaigner whose son was murdered by loyalist paramilitaries, will be heard on Thursday.

There was a further hearing in Belfast on Monday of appeals from other Northern Ireland cases involving claims that a no-deal Brexit and the imposition of a hard border would damage the Northern Ireland peace process. Judgment was reserved. Those involved may apply to the supreme court for a separate hearing later this month if they lose.

The main claimant in the English case is the businesswoman and legal campaigner Gina Miller. She brought the first article 50 challenge in 2016 that resulted in victory when parliament, not the government, was confirmed to have the right to authorise the UK’s departure. Her latest action is consequently known in legal circles as Miller (No 2).

Timeline The plan to prorogue parliament and the court cases against it Show Hide

The story breaks The Observer breaks the story that Boris Johnson has sought legal advice on closing parliament for five weeks Leaks spread Other media organisations begin to receive leaks that Johnson will make a statement on prorogation Visit to Balmoral Three privy counsellors, including Jacob Rees-Mogg, travel to Balmoral to tell the Queen of the prorogation plan. Cabinet ministers are informed by conference call Protests and protestations Tens of thousands protest against prorogation. Cross-party group of MPs steps up preparation for blocking no deal when parliament makes a brief return Parliament returns Parliament returns and the prime minister loses six votes in six days. MPs vote to prevent a no-deal Brexit, and refuse Johnson's attempts to force them into a general election. Gina Miller case fails Legal campaigner Gina Miller vows to continue her “fight for democracy” after the high court dismissed her claim that the prime minister acted unlawfully in giving advice to the Queen to suspend parliament at a time of momentous political upheaval. Parliament dissolved Parliament is dissolved amid chaotic scenes as some MPs hold up signs saying they have been silenced, try to prevent Speaker John Bercow leaving the chamber, and sing the Red Flag. Scottish court ruling The court of session in Scotland rules that Boris Johnson’s decision to prorogue parliament for five weeks was unlawful. The case will go to the supreme court. Supreme court hearing The Supreme court begins three-day hearing to join together all the appeals and legal challenges to the prorogation. Supreme court finds prorogation was unlawful The judges unanimously decided that prorogation was justiciable, and it was in the power of the court to rule on it. They additionally found that the prorogation was unlawful, as it had the effect of preventing parliament from being able to carry out its constitutional functions. The court found that the prime minister’s advice to the Queen was unlawful, void and of no effect. Their unanimous judgement was that parliament had not been prorogued. Parliament goes back to work.

She will be represented again by Lord Pannick QC, one of the leading constitutional lawyers of his generation. He will open submissions on Tuesday morning and be followed in the afternoon by Lord Keen. Both are applicants seeking to overturn judgments in London and in Edinburgh respectively.

Eadie, Pannick and Keen are all, coincidentally, in the same London chambers, Blackstone Chambers, which specialises in constitutional cases.

The Scottish legal team will be led by Aidan O’Neill QC, acting for a cross-party group of 75 MPs and peers including the SNP MP Joanna Cherry QC. Their action has been funded by Jolyon Maugham QC’s Good Law Project.

Other politicians, MPs, human rights groups and individuals have applied to intervene in the three-day hearing. Those allowed to intervene will present their claims on Thursday afternoon.

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Many campaigners were disappointed to be excluded from the London high court hearing earlier this month, including a barrister, Roger Harrison, who told the Guardian he had to pay a court fee of £255 even though he was denied permission.

It is not clear whether there will be legal skirmishes over disclosure. Michael Gove, chancellor of the Duchy of Lancaster, has refused to comply with MPs’ requests for messages relating to the suspension of parliament sent by Johnson’s senior adviser, Dominic Cummings and various other aides.

Gove said it would be “singularly unfair to the named individuals”. Dominic Grieve QC, the former attorney general, told MPs last week he had information from public officials that the correspondence contained a “scandal”.

The supreme court justices who will hear the case are: Lady Hale, president; Lord Reed, deputy president; Lord Kerr; Lord Wilson; Lord Carnwath; Lord Hodge; Lady Black; Lord Lloyd-Jones; Lady Arden; Lord Kitchin; and Lord Sales.

Permission has been given for six interveners in the Gina Miller case. They are: the lord advocate for the Scottish government, Raymond McCord, the counsel general for Wales, Sir John Major, Baroness Chakrabarti, the shadow attorney general, and the Public Law Project.



