Lord Pannick versus Boris Johnson. Here in the antiseptic calm of the Supreme Court Gina Miller’s barrister set about impugning the Prime Minister’s motives.

Outside in the sunshine the demonstrators shouted and waved their placards. In court, the more deadly weapon of polite insinuation was deployed.

Johnson, Lord Pannick contended, had exercised his power to prorogue Parliament for “an improper purpose”. Miller sat behind Lord Pannick, looking a model of propriety.

The forces of propriety – metropolitan propriety, at least – were intent on destroying Johnson. The majesty of the law was to be used to trample this improper figure under foot.

The Prime Minister would be thrown out of respectable society. The Dinner Party, as the late, great Frank Johnson (no relation) used to call it, would never again allow this scoundrel to darken the fashionable repasts over which it exchanges received opinions.

For the Prime Minister’s motive, according to Lord Pannick, is “to silence Parliament”, and “it is an improper purpose for him to be motivated by a wish to avoid parliamentary control”.

It was also “an invalid purpose”. Jacob Rees-Mogg had gone to Balmoral where the Queen had no choice but to give her formal approval to this abuse of power.

Lord Pannick referred to page 373 in the trial bundle, where we would find “Mr John Humphrys interviewing Mr Jacob Rees-Mogg”.

Those of us who are not lawyers hoped this exchange would clarify the issues. But the 11 judges, sitting behind a curved modern wooden desk, could not find it, because the numbering on their bundles did not correspond to the numbering on Lord Pannick’s.

Lady Hale, the President of the Supreme Court, said there was “always trouble” with the bundles. After a period of confusion, it emerged that by adding 63, the numbers in the judges’ bundles could be made to correspond to those in Lord Pannick’s.

No trace of panic appeared on Lord Pannick’s features. He looked quite pleased with himself as he said in a smooth tone, “I don’t know why the numbering is different and I’m very sorry.”

He called in evidence “a Sky News interview with Boris Johnson by the journalist Sam Coates”, in which the Prime Minister had said it would be harder to achieve Brexit “if our friends and partners on the continent” thought Brexit could be blocked by Parliament.

This, Lord Pannick said, was “strong evidence as to the Prime Minister’s motive”. He added with a satisfied air that it was “a remarkable feature of these proceedings that the Prime Minister has not made a witness statement”.

It was possible to “draw an inference” from this failure to make a statement.

Lord Pannick and his client want us to believe the worst of the Prime Minister. They are convinced he wants to drive through Brexit in accordance with the referendum result.

They think there should be a law against this, or at least a judgment that hinders it. Such a desperado has no place in polite society.

Lady Hale said at the start of the hearing that “we are not concerned with the wider political issues”. The judges are just there to decide “a serious and difficult question of law”.

This being so, it seemed strange to hear Lord Pannick laying such stress on the Prime Minister’s motives. Is a court of law really the place for these to be determined? Might not the court of public opinion be more suitable?