There is a famous Sherlock Holmes mystery that has given to the world an idiom: The curious case of the dog in the night that did not bark when it should have done.

UK politics is undergoing one of its periodic upsets, as the governing Conservative Party once again dispatches a leader without reference to the electorate. As David Cameron, Theresa May and now Boris Johnson have discovered, the historic and traditional general election — which the UK makes much of in terms of democracy-building and soft power the world over and which removes a prime minister by way of an opposition victory with nothing more dramatic than a handshake and a removals van at 10 Downing Street — is fading into history, as leaders find their party colleagues more lethal than the voters.

But as the mechanics of the last week are being absorbed, the UK still finds itself with serious unresolved questions and a glaring gap in the constitution. Johnson has been forced to give up his leadership position, but still sits in Downing Street, appoints new Cabinet members and ministers, and prepares to oversee the government until a successor is found, in many weeks’ time. In this, he is following precedent, as both May and Cameron did the same. But as critics are pointing out, the circumstances of removal are very different.

Neither of Johnson’s predecessors lost office because of their personal qualities. Nor did they have nearly 60 of their ministers resign, many quoting in their letters leaving office their deep concern over the loss of integrity in the government and in Johnson personally based on a series of scandals and, crucially, the willingness of the prime minister’s machine to send ministers out to the media with explanations of events that, to put it politely, later turned out to be inaccurate. This meant Cameron and May could be relied upon to handle their declining responsibilities fairly and with the confidence of their colleagues. The distrust around 10 Downing Street currently is of a different order.

How, in these circumstances, a government can function is unclear. What if there is a contentious foreign policy issue to be clarified? Is it made or merely ducked for a while? Few of the ministers who resigned have so far been recalled. Most are being replaced, but they must wonder for how long. How is the independent civil service supposed to function, especially when facing difficult decisions that may not be able to wait for the currently anticipated six weeks or so that it will take to resolve the issue of who comes next?

But the dog that is not barking now is the Labour opposition. Three elements are needed for a government to lose office after a lengthy period of governing. Firstly, it must turn on itself. This seems possible, as the internal debate in the Conservative Party turns to a serious examination of the key economic choices ahead and the question of what Conservatives really want the UK to be post-Brexit. The sides are already lining up. The public will tolerate, and indeed expect, a robust debate on policy, but will not want such a debate to appear to exclude them.

Labour might reinforce a sense that it is the Conservative Party, not just the present incumbent, that cannot be trusted.

Alistair Burt

Secondly, the public must have made its mind up that the government has to go, no matter what. We seemed to be close to that, as evidenced by recent by-election results. And this must surely now be tested by another following the incident concerning the former deputy chief whip.

And thirdly, the leader of the opposition has to be seen by the public as ready to take over, to be the “prime minister-in-waiting,” which Tony Blair was, but which the present leader of the opposition is not — yet.

There is a hesitancy about the opposition, which their senior members admit. They do not know if the loss of the prime minister will affect their chances of electoral success more or less than the Conservative Party, which will reshape itself after these events, as it has successfully done in such circumstances in the past.

But the gap in the constitution might play into the opposition’s hands and allow it to make a serious challenge to the handling of the transition. If it can point to a problem in the next six weeks as having been magnified by the arrangements around the prime minister staying in office, while he has a deputy available who is not standing in the contest and does not suffer from the same reputational issue, then Labour might reinforce a sense that it is the Conservative Party, not just the present incumbent, that cannot be trusted. This would constitute a grave risk to the Conservative Party, which it would do well to take action to prevent.

The loss of Prime Minister Johnson has raised comment in many capitals. The eventual resonance pointing toward a future government remains unclear, and diplomats will be working overtime for some weeks yet.

Alistair Burt is a former UK Member of Parliament who has twice held ministerial positions in the Foreign and Commonwealth Office — as Parliamentary Under Secretary of State from 2010 to 2013 and as Minister of State for the Middle East from 2017 to 2019.

Twitter: @AlistairBurtUK