The argument about whether Boris Johnson would have to resign if he lost a confidence vote is continuing to rage at Westminster. There is, though, an angle to this argument that is being neglected.
Right now, the Labour leadership is clear that it won’t back anyone other than Jeremy Corbyn to be prime minister. This means that even if Boris Johnson lost a no-confidence vote, it is not clear who could command the confidence of the Commons. With no alternative government ready to go, then an election would be the obvious answer.
Things become more complicated if an alternative government could somehow be formed. In these circumstances, there would be more pressure on Boris Johnson to resign. But given that the fixed term parliament act is meant to see a parliament complete its term, that pressure would be less if this alternative government was itself planning to go to the country as soon as it had written a letter to the EU Commission requesting an extension.
It would be far more difficult for Johnson to deny the claim of any alternative government that could try and make it to 2022, when the next election is meant to be held. It is, though, almost impossible to see how such an alternative government could be put together.
Of course, if there is a majority in the Commons for something it can generally find a way. It is conceivable, for example, that the Commons could legislate for a snap election with a short campaign to get a new parliament—and then government—in place before October 31. Right now, though, it is far from clear how all of this constitutional brinksmanship is going to play out.