19:36

The three Scottish appeal judges who ruled Boris Johnson had unlawfully prorogued parliament have bluntly accused the prime minister of misleading voters on his true reasons for suspending parliament.

They agree unanimously it was to prevent proper scrutiny of his Brexit strategy – and for no other reason – in their official rulings issued by the Scottish courts late on Thursday afternoon.

Read the judges’ opinion in full here (pdf).

Lord Carloway, the lord president, said prorogation was sought “in a clandestine manner” when Downing Street knew 75 MPs and peers were taking the government to court to block it.

No 10 also did this knowing prorogation would stymie debate about Johnson’s Brexit plans and then gave the court no clear reason to justify prorogation, as well as the five-week period Johnson got from the Queen, which they described as an “extraordinary length of time.” Carloway said:

The circumstances demonstrate that the true reason for the prorogation is to reduce the time available for parliamentary scrutiny of Brexit at a time when such scrutiny would appear to be a matter of considerable importance, given the issues at stake. [Put] shortly, prorogation was being mooted specifically as a means to stymie any further legislation regulating Brexit.

Lord Drummond Young is particularly blunt, arguing that the UK government’s failure to provide the Scottish court with any valid reasons for proroguing Westminster for five weeks supported their conclusions it was unjustified.

If no reason is given, in the present circumstances, I am of opinion that the decision to prorogue parliament for five weeks out of the seven remaining before the United Kingdom is scheduled to leave the European Union leads inevitably to the conclusion that the reason for prorogation was to prevent parliamentary scrutiny of the government. I find it impossible to see that it could serve any other rational purpose.

Lord Brodie, the third judge, said that, despite the weight courts need to give to the royal prerogative and a government’s right to use procedures to suit its purposes, this was an “egregious” case of misuse of prorogation.