‘Which is to be master?’

John Locke, commonly seen as a founding father of liberalism, also foretokened the political thought of the Nazi jurist Carl Schmitt. In chapter 14 of his Second Treatise, Locke turns to the notion of the prerogative: 'This power to act according to discretion, for the public good, without the prescription of the law, and sometimes even against it, is that which is called prerogative ... therefore there is a latitude left to the executive power, to do many things of choice which the laws do not prescribe.' This is Locke's version of Schmitt’s Ausnahmezustand, usually translated (no version is perfect) as ‘state of exception’, which obtains when the sovereign deems it necessary to override the law.

Schmitt's version of the idea is sometimes apposed with Article 48 of the Weimar Constitution, disastrously invoked by Hindenburg after the Reichstag fire in 1933 and exploited by Hitler to hasten dictatorship. This is, to be sure, the sort of thing that gives emergency powers a bad name. It often happens on the plea of defending the constitution, as with the US National Socialist Movement, who have reportedly dispatched plain-clothes vigilantes to monitor supposed voter fraud at today's polls on Trump's behalf. Locke's version cites, more agreeably, the Ciceronian tag ‘Salus populi suprema lex’, though that leaves the small matter of who authoritatively determines what the public good is. For example, who decides whether the public good lies in Britain's remaining part of the EU? The British public themselves were recently asked this question, and various reasons have since been given – before they answered, not so much – for not treating their answer as authoritative.

Last week's high court ruling that the government needs parliamentary assent to trigger Article 50 of the Lisbon Treaty was widely greeted, by Remainers at least, as a reaffirmation of the rule of law over the use of the prerogative. Some commentators who endorsed the verdict cited A.V. Dicey, the 19th-century theorist often invoked as an authority on the UK constitution. Their lordships quoted Dicey too: ‘The judges know nothing about any will of the people except in so far as that will is expressed by an Act of Parliament.’

Unfortunately, Dicey is not entirely at one with himself on this issue. On occasion, he remarks, there may be ‘fair reason to suppose that the opinion of the House is not the opinion of the electors … A dissolution is allowable or necessary whenever the wishes of the legislature are or may fairly be presumed to be different from the wishes of the nation.’

Brexiters might fairly take this as describing the situation that will come about if the government’s appeal to the Supreme Court is thrown out and the Commons refuses to trigger Article 50; it might be thought of as Dicey’s version of the exception that proves the rule of law.

Remainers have pointed out that Brexiters campaigned for Westminster to take back control; Brexiters have observed that Remainers have suddenly grown fond of the parliamentary sovereignty they'd happily ceded to the EU hitherto. Inconsistency is the warp and woof of our collective lives. This seems as true of the three High Court judges who handed down last week's ruling. ‘The most fundamental rule of UK constitutional law is that the Crown in Parliament is sovereign,’ they said, and ‘there is no superior form of law than primary legislation.’ This rule is so fundamental that it has only ever known one exception: the European Communities Act 1972, ‘which confers precedence on European law’.

Richard Rorty, flagging philosophers' tendency to nod at their own inconsistencies, liked to quote J.L. Austin: ‘There's the bit where you say it and the bit where you take it back.’ Whose exception? Which authority? ‘The question is,’ Alice says to Humpty Dumpty, ‘whether you can make words mean so many different things.’ No, he says, ‘the question … is which is to be master – that's all.’ Or, if not all, it’s always a question worth asking.