For those who fear that resort to referendums might erode parliamentary democracy, the recent past provides unhappy confirmation. The hysterical cry of “enemies of the people” against the High Court’s decision that only parliament is entitled to make and repeal laws, now being reviewed by the Supreme Court, demonstrates that some Brexiters do not care about parliamentary sovereignty. Their cause is rather dictatorship of the majority.

The phrase “enemy of the people” — used to turn opponents into outlaws — has an ignominious pedigree. During the French Revolution, Robespierre threatened “les ennemis du peuple” with death. The Soviet Communists labelled opponents “vrag naroda”. The Nazis labelled them “Volksverräter”. The aim was always the same: to establish a dictatorship in the name of the people, thereby entitling the rulers to deprive opponents of freedom, even their lives, as the people’s condemned enemies.

It is significant that the label “enemy of the people” is now being employed in an assault on the probity of the judiciary. The phrase has usually been used to justify depriving opponents of the protection of due process. It is the rhetorical arm of an assault on the rule of law. What could make more sense, then, than using it to attack courts directly?

This, needless to say, is not how Brexiters present it. They present it as a defence of parliamentary sovereignty against judicial attack. Yet the High Court merely ruled that only parliament and not the executive, exercising the royal prerogative, may remove rights from the people. This is not an offence against parliamentary sovereignty, but a defence of it. It is worth remembering that, in his play, An Enemy of the People, Henrik Ibsen thought the people’s “enemy” was correct and his opponents wrong. This is true now, too.

In a recent column, the former Conservative leader, Iain Duncan Smith, an influential and passionate Brexiter, asks why “unelected judges have the right to supersede the wishes of the elected members of parliament, and through them the government”. Yet that is not at all what the court did. It ruled that the government has no right to ignore parliament when triggering the Article 50 leaving process. Mr Duncan Smith’s argument is that parliamentary sovereignty allows the executive to ignore members of parliament altogether. That is to enthrone the principle while emptying it of most of its content.

How could Mr Duncan Smith reach such a surprising conclusion? The answer lies in the referendum. His view is that, since 17.4m voters chose Leave last June, “the people” have spoken. All that is now needed is for the executive to implement that choice, untrammelled by parliament. Use of referendums to bypass any and all institutional constraints on the exercise of executive power has a long and deeply illiberal, indeed anti-democratic, history. Louis Napoleon established a dictatorship by means of referendums in the 19th century. Mussolini and Hitler did the same thing in the 20th century. In all these cases, charismatic rulers legitimised the overthrow of restraints on their power by appealing to the people in this way.

Until recently, I thought this was inconceivable in the UK. I am rather less confident now. The view that the executive not only can, but must, implement the outcome of the referendum, as interpreted by influential newspapers, regardless of the views of the 16.1m people who voted Remain and of elected members of parliament, is a form of authoritarianism. It exalts what the 19th century French liberal Alexis de Tocqueville called “the tyranny of the majority”. The creators of the American constitution had a similar fear.

In practice, only a government can implement the will of such a majority. As constraints upon the government are discarded, in the name of the majority, the government may become a dictatorship that rules in the people’s name. Its popularity is often used to justify the elimination of restraints and even the suppression of opponents. An assault on judicial independence is often a part of such a story. That is a remote danger in the UK today. But we must not ignore it.

The resort to referendums as a way of deciding constitutional questions undermines parliamentary democracy. Nevertheless, the outcome of the EU referendum has to be accepted.

Even so, the referendum does not implement itself. It does not entitle the government alone to decide what Brexit means. It certainly does not justify denigrating as “enemies of the people” judges who rule that parliamentary oversight is, after all, a central element of parliamentary sovereignty. This intimidation of the judiciary is disturbing and disgraceful.

martin.wolf@ft.com

Letters in response to this column:

Referendum gave no clue as to what Leave voters had in mind / From Dr William Dixon, London, UK

Leave vote actually strengthens UK’s parliament and judiciary / From Michael Fernandes

The state has a right — and a duty — to speak up in defence of the judiciary / From Edward Mortimer