The title is from the Case of Proclamations which dates back to James I ironically – or indicatively? – England’s first Scottish king.
So the idea that the prerogative to prorogue Parliament is not ‘justiciable’ should be for the birds.
So far, the current case in the Supreme Court has mentioned nothing of this – perhaps they hope to base their case on more recent precedents (though in the past it has been cited by the divisional court) – or as I hope, I now think folornly, simply on the Rule of Law.
There are nonetheless some really lovely quotes from Gina Miller’s counsel, Lord Pannick:
I am not challenging the existence of a power to prorogue. But the Prime Minister is not entitled to prorogue for period so long that it will have the effect or purpose of frustrating the constitutional principle of parliamentary sovereignty and supremacy over the executive.
The basic principle is that Parliament is supreme. The junior partner, the executive, cannot validly use its constitutional powers from preventing the superior body from performing its constitutional functions, especially when that function is the scrutiny of the junior partner.
And when he is asked whether the courts should intervene when Parliament has declined to pass a vote of no confidence in the Government he replies that the
Executive [ie the government] is answerable to Parliament in matters of politics, but to the court in matters of law. Confidence is immaterial.
Irony of ironies, I suggest that we owe this child of the Empire whether or not she succeeds (and I have to declare that I contributed to the crowdjustice fund, so I rather hope she does) once again, our heartfelt thanks.