“A constitutional outrage”, declared the Speaker, John Bercow; “a very British coup”, said the shadow chancellor, John McDonnell. Not to be outdone, Nicola Sturgeon added “the day any semblance of British democracy died”. Some have compared the situation to 1628, when Charles I prorogued parliament before dispensing with its services entirely. But Charles I was not, unless the history books are grievously mistaken, faced with the problem of implementing the outcome of a referendum.

It is time perhaps to tone down the rhetoric and consider the facts. The five-week prorogation appears longer than it is because it includes the three weeks of the party conference season, when parliament does not normally sit. Parliament therefore loses two weeks. In 2014 there was a longer prorogation of 20 days, though that included the period of the European parliament elections and the Whitsun recess.

But of course the objection to prorogation has less to do with the time lost than its alleged purpose, frustrating the will of parliament. That the prime minister has unreasonably used his prerogative power to advise the Queen will, no doubt, form the basis of an approach to the courts. Whether that approach succeeds or not, the political dilemma remains: that parliament has willed the end of Brexit without willing the means.

MPs have rejected the government’s flagship policy without providing any alternative

In 2017, parliament empowered the prime minister to invoke article 50 by the massive majority of 384 votes when MPs passed the European Union (Notification of Withdrawal) Act. But in 2019, the Commons rejected the withdrawal agreement three times. The EU has responded that the agreement cannot be renegotiated. In logic, therefore, the only way to implement Brexit is without a deal. Since every member of the cabinet except for Priti Patel and Theresa Villiers voted at least once for the deal, they can hardly be blamed for the fact that a no-deal Brexit now seems the only logical alternative.

The Commons, it is often said, is opposed to a no-deal Brexit. But it is also opposed, as shown by its votes, to a second referendum (which it rejected by an absolute majority) and membership of the internal market and the customs union, and it has shown no disposition to revoke article 50. The only positive policy MPs have supported is that embodied in the Brady amendment, calling for the Irish backstop to be replaced with alternative arrangements, something the EU declares it will not countenance. MPs may claim that they are losing vital sitting days in September and October. But they have had three years to come up with an alternative policy. They have failed to do so.

Opponents of the government seek an extension of the Brexit date. But that is not in itself a policy. Two previous extensions have achieved nothing. Why should a third prove any different? Would MPs then accept the withdrawal agreement? Do they have the leverage to persuade the EU to alter its stance? Without an answer to these questions, a further extension is a mere empty aspiration. And were parliament to pass legislation preventing Britain leaving the EU without a deal, Brexit could be delayed for ever, since the Commons would then be free to reject every deal presented to it.

The truth is that 650 MPs cannot make policy. Only the government can do that. The role of parliament is not to govern but to scrutinise those who do. That is especially the case with the treaty-making power. Indeed, parliament has not rejected a treaty since 1864. And parliament is in no position to renegotiate a treaty. It has never in modern times sought to do so. The EU can negotiate only with governments, not with a motley alliance of MPs who are themselves divided between remainers and soft Brexiteers.

MPs have rejected the government’s flagship policy without providing any alternative. It is enabled to pursue this course because of the wretched Fixed-term Parliaments Act. Without that, Theresa May could have declared the deal a matter of confidence. That was what Edward Heath did in 1972 when he threatened a dissolution unless the European Communities bill was passed, securing in consequence a majority of eight on its second reading. Had May been able to do the same, the rebels would either have come to heel or there would have been a general election. But the threat of dissolution has now been removed from the prime minister’s armoury.

No-deal Brexit: cross-party rebel alliance gears up for clash with Johnson Read more

Once MPs have rejected the flagship policy of any government, their obvious recourse is to remove it and replace it with one more to their liking. That requires a successful no-confidence vote and either an alternative government chosen from the existing House of Commons or, more likely, a general election so that the people can arbitrate. But Boris Johnson’s opponents seem unsure that they could carry such a no-confidence vote. So there is an institutional deadlock that threatens to prevent Johnson from breaking the Brexit deadlock. That can now be broken only by the EU. In fact I suspect that the long prorogation is directed as much at the EU as Westminster, to convince the EU that parliament will not be able to stop a no-deal Brexit.

Looking at the sorry performance of the House of Commons elected in 2017, it is difficult to avoid remembering Winston Churchill’s condemnation of the parliaments of the 1930s as being “decided only to be undecided, resolved to be irresolute, adamant for drift, solid for fluidity, all-powerful to be impotent”. Parliament has shown itself not to be the solution to Brexit but the problem.

• Vernon Bogdanor is professor of government at King’s College London