Legal charity the Public Law Project has been given permission to intervene in the Supreme Court challenge to the prorogation of parliament. Hearings in Miller v The Prime Minister and Cherry v Advocate General for Scotland open at the court today. 

The Public Law Project will argue that Boris Johnson acted unlawfully because he did not consider the impact on parliament’s ability to scrutinise the secondary legislation required for an orderly Brexit. The charity's director, Jo Hickman said: 'The effect of prorogation is that statutory instruments affecting customs, financial services, food hygiene, banking regulations, animal health, air transport and product safety are being pushed through under an "urgent" procedure.'

This could mean they become law without parliamentary oversight until after exit day, Hickman said. 'This urgency is of the Prime Minister’s own making. His actions pave the way for law-making by executive order, rather than by elected representatives.' 

Public Law Project said it does not take a position on leaving the EU. 

Five other parties including, the lord advocate on behalf of the Scottish government, the counsel general for Wales and Baroness Chakrabarti are intervening in the case, which is being heard by 11 Supreme Court justices under Lady Hale. 

The court will rule on two issues:

  • Whether the prime minister's decision to advise the Queen to prorogue parliament is justiciable in the courts; and
  • If the decision is justiciable and the appeal is not academic, whether that advice was lawful.

The hearing is scheduled for three days.