Lawyers arguing against the suspension told a historic hearing at the Supreme Court that the prime minister had wanted to “silence” parliament because he feared that MPs and peers would block “the furtherance of his political aims” – namely delivering Brexit with or without a deal by 31 October.
As the row over Brexit once again ended up in front of the UK’s most senior judges, lawyers for the government refused to rule out Mr Johnson simply proroguing parliament again if the original suspension is ruled unlawful and MPs and peers resume their sitting.
They insisted that Mr Johnson had not abused his power to suspend parliament and claimed that, even if he had, it was not a matter for the courts.
The Supreme Court hearing was called after a series of legal challenges were launched following the highly contentious move. Anti-Brexit campaigner Gina Miller brought a case in England, while a cross-party group of MPs and peers launched a separate challenge in Scotland. A third case was heard in Northern Ireland.
The English and Northern Irish courts ruled with the government, while Scotland’s Court of Session decided that the suspension of parliament was unlawful.
The Supreme Court will hear three days of evidence before making a ruling that could have a seismic impact on the future of Mr Johnson’s government and the fate of Brexit.
Sir John Major, the former prime minister, is expected to address the court in support of Ms Miller’s case on Thursday.
Opening the hearing on behalf of Ms Miller, Lord Pannick, a prominent barrister, told the 11 judges that “no prime minister has abused his power in the manner in which we allege in at least the last 50 years.”
He said Mr Johnson had acted unlawfully by advising the Queen to prorogue parliament for an “exceptional” length of time, telling the court: “The exceptional length of the prorogation in this case is strong evidence that the prime minister’s motive was to silence parliament for that period because he sees parliament as an obstacle to the furtherance of his political aims.”
Lord Pannick said the five-week length suggested that the reason given for the suspension by the government – that it was necessary to bring forward a Queen’s Speech in early October – was not the real one.
If it was, he said, then Mr Johnson “would not have recommended to Her Majesty a prorogation for a period of longer than five weeks, but he would have recommended a substantially shorter period, as has occurred on every occasion in the last 40 years”.
Instead, he claimed, Mr Johnson had acted out of concern that parliament would try to block his Brexit plan.
But even if this was not Mr Johnson’s motive, he said, the decision had the same consequence of removing parliament’s power to hold the government to account just weeks before the Brexit deadline – a crucial period when it was “self-evident” that MPs and peers would want the ability to do so.
That was a clear breach of the principle of parliamentary sovereignty and should be deemed unlawful, he claimed.
The QC also pointed to Mr Johnson’s decision not to provide a witness statement to the court, claiming that it should be inferred from this that the prime minister’s “advice to Her Majesty was motivated or at least strongly influenced by the prime minister’s desire to prevent the risk, as he saw it, of parliament damaging government policy”.
He said providing such a statement would “inevitably” have led to a request for the prime minister to be cross-examined in court and noted that it would have been a contempt of court “for such a witness statement not to tell the truth”.
Responding for the government, Lord Keen, the advocate general for Scotland, said Mr Johnson had acted fully within the law. He insisted that parliament was suspended to allow for a Queen’s Speech.
He said it was not true that the decision had resulted in parliament being closed for five weeks, because much of that period was covered by the usual three-week parliamentary recess for party conferences.
As a result, he said, Mr Johnson’s decision meant “that only seven sitting days would be lost to parliament if it was prorogued during that period”.
However, in a significant exchange under questioning from Supreme Court judge Lord Kerr, Lord Keen appeared unable to explain why parliament had needed to be prorogued in early September to allow for a Queen’s Speech in mid-October. He was forced to accept that a suspension beginning as late as early October could still have resulted in the Queen’s Speech taking place on the same day – 14 October.
Crucially, it is unclear what will happen if the court rules that Mr Johnson’s advice to the Queen was unlawful.
While he insisted that the government would abide by the ruling, Lord Keen refused to rule out Mr Johnson simply proroguing parliament again.
Asked whether this was a possibility, he replied: “I’m not in a position to comment on that.
“That will have to be addressed by the decision maker.”
One of the judges, Lord Carnwath, asked for the issue to be clarified in writing on behalf of the prime minister.
While dozens of pro-Brexit and anti-Brexit protesters clashed outside the court, other members of the public queued for hours to secure front-row seats at the historic proceedings.
Millions more tuned in online, with the Supreme Court live stream accessed 4.4 million times during the morning session alone. Officials said it was typically used around 20,000 times a month.
At the centre of the complex case is the question of whether the decision to prorogue parliament is justiciable – in other words, a matter for the courts.
Lord Pannick insisted that it was “well-established that the executive is answerable to parliament for matters of politics and answerable to the courts for matters of law”.
He said that, if the court rules that the issue is not justiciable, the judges would effectively be saying that there is nothing to stop the prime minister suspending parliament for as long as he or she saw fit – a deeply worrying precedent, he claimed.
But Lord Keen said parliament had had the opportunity to legislate to block the prorogation and did not do so, and that the issue was not a matter for the courts.
He said: “Insofar as the Inner House [of the Court of Session] has sought to declare the prorogation unlawful, I will take no issue with their order. But, insofar as they purport to declare that the prorogation is null and of no effect, I submit that they have simply gone where the court could not go.”
The issue is one of the central questions that the 11 judges will have to decide on later this week. Downing Street will be watching the case closely, knowing the verdict could have a major impact on the future of Brexit – not to mention that of Mr Johnson’s government.
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