On Wednesday, the morning after the unanimous decision of Britain’s Supreme Court in Miller v The Prime Minister, Jonathan Sumption appeared on Adam Boulton’s All Out Politics program on Sky News UK. Lord Sumption retired from the Supreme Court late last year. Earlier this year he delivered the Reith Lectures on BBC Radio 4.

Boulton began the interview by reminding Sumption that he had raised questions about “the expanding empire of law” in his lectures. In view of this, the Sky News UK presenter wondered if Sumption had any qualms about the Supreme Court judgment that Prime Minister Boris Johnson’s decision to prorogue (temporarily close down) parliament was unlawful and, consequently, had not happened.

It turned out, however, that Sumption was happy with the ­decision of the Supreme Court. Asked about newspaper comments that judges had taken over politics in defying the will of the people and the government, Sumption stood up for his former judicial colleagues. In doing so he stated a novel legal principle.

In the referendum in June 2016, 17.4 million British voters (52 per cent) supported the view Britain should exit the EU — Brexit. The problem was, most British parliamentarians wanted the ­nation to remain in the EU. This was the case before the June 2017 general election and remains so today. In short, most of the electorate is at odds with the position of most of their representatives.

According to Sumption, there’s no problem here. He maintained that the judgment handed down by Lady Hale, president of the ­Supreme Court, had “simply ­restored on a legal basis constitutional principles that were previously a matter of political convention”. Sumption put it this way: “It’s the job of the Supreme Court to determine what our constitutional rules are. But I would say, to those who say that this (judgment) is ignoring the 17.4 million, that our constitution is based on the proposition that 52 per cent cannot have 100 per cent of the spoils. They have to engage with the rest and parliament is the best mechanism that we have for ensuring that they do.”

This despite the fact most Brits decided to exit the EU in June 2016 and that all the key parties at the June 2017 general election promised to implement the result of the referendum.

Needless to say, Sumption did not advance any legal authority for his assertion.

Britain does not have a written constitution and there is no legal convention that prescribes that the judiciary should ensure that the parliament engage between those who support and those who oppose a Brexit moment. Moreover, it is unlikely he would advance such a proposition had Remain, not Leave, prevailed at the referendum.

Certainly, these days, the ­Supreme Court is Britain’s superior court. Its decision in Miller v The Prime Minister has set a precedent that the judiciary can intervene to thwart advice from a prime minister to the Queen to prorogue parliament. Hale and her colleagues stated that a prorogation of up to 34 days was unlawful but did not state what time frame would be lawful.

The judges declared they did “not know what the Queen was told” by Johnson. Also the court stated it expressed “no view” as to whether “Her Majesty was other than obliged by the constitutional convention to accept” her prime minister’s advice.

The Supreme Court’s decision was delivered on an appeal from the High Court of Justice in Gina Miller v The Prime Minister. There Lord Burnett (Lord Chief Justice of England and Wales), Sir Terence Etherton (Master of the Rolls) and Dame Victoria Sharp (president of the Queen’s Bench Division) came to a unanimous decision. Namely that “the decision of the Prime Minister to advise Her Majesty the Queen to prorogue parliament is not justiciable in Her Majesty’s courts”.

Clearly the High Court did not believe the judiciary should intervene between the Queen and her Prime Minister.

However, the Supreme Court has no doubt about what prime ministerial advice to the Queen is lawful and what is not. This puts Britain’s judiciary in the midst of British politics. This is not a wise place to be at the ­moment.

Sumption was educated at Eton College and Magdalen College Oxford. Johnson’s background is Eton and Balliol at Oxford. The former upholds the rights of the 48 per cent; the latter believes in implementing prom­ises to uphold the will of the 52 per cent. But Johnson is in a minority among Eton/Oxford types.

There is a view in Britain that the establishment — a term popularised by journalist Henry Fairlie six decades ago — is determined to remain as part of the EU. This is not the old concept of Britain with a delineated upper, middle and working class. Those times have gone. Yet a division remains between self-declared progressives who regard themselves as European, and those who identify with England and its traditions.

In such an environment it is unwise for the Supreme Court to wade into politics and announce a decision in favour of wealthy business woman Gina Miller and former Tory prime minister John Major. In the High Court’s view an argument between Miller/Major and Johnson as to what the Queen should have done with respect to parliament was no business of the judiciary. However, Hale and her fellow judges found the dispute was justiciable having discovered precedents as far back as 1611.

The decision of the Supreme Court has damaged the Westminster system of government that traditionally had voters electing politicians who chose a government from among their peers. Now the Speaker of the House of Commons, John Bercow, is behaving as if he is the prime minister.

Johnson has been accused of being a dictator. But the parliament will not allow him to call a general election — presumably because there is concern that, once again, the 52 per cent (perhaps more) will prevail over the 48 per cent (or less).