Who could have seen this coming, eh? Who could have guessed that a man whose entire career — entire life — had been based around ignoring conventions and rules would turn out to have ignored rules and conventions?

It’s funny, of course. It’s generally satisfying when people turn out to be exactly who you thought they were. There is also great pleasure in reflecting on all the Government Insider briefings that he wouldn’t be fined, that he’d got lawyers on the case, that Number 10 is a unique situation, or a royal palace, or actually part of the ancient kingdom of Burgundy. All those turned out to be worth exactly as much as they obviously were when they were written up.

From the moment that the Metropolitan Police decided that, on balance, they probably could investigate crimes that had taken place in the past, and that photographs and witnesses and things police officers had seen did, they supposed, count as evidence, it has always felt inevitable that Boris Johnson would be fined over lockdown parties.

But it’s also tremendously wearying. Johnson’s strategy with scandals has long been not to prove his opponents wrong but to outlast them. He could stay awful for longer than they could stay outraged.

So, we move on to a new phase. Presumably the argument will be that Johnson didn’t mislead parliament when he said he knew nothing about parties because in his mind they weren’t parties. This is in no way undermined by his not initially knowing which party he’d been fined for because there were, frankly, so many possibilities.

There is never a good moment to be dumping a disgraced prime minister

He is surely not, as some wildly claimed, the first prime minister in history to break the law. And the law he broke wasn’t murder. This was, as surely someone is typing even now in a “lines to take” draft, more like a speeding ticket. But it was the one law that ministers including both Johnson and Rishi Sunak went on TV night after night to tell us we had to obey. The lives of our fellow citizens were in our hands, they said.

You may not believe that. You may think that lockdowns were a mistake, that Johnson should have been like the mayor in Jaws, or listened to the scientists of Great Barrington, that the harms were greater than the benefits. This is all beside the point. It was the law. They decided on the law, they passed the law, they told us again and again and again that we all had a public duty to follow the law, and then they broke the law. Repeatedly.

None of this is difficult: people who make the law should follow the law.

Which brings us to the only people with the power to do anything about this: Conservative MPs.

They bleat that the situation has changed since January, and that it’s not a good moment to change leaders. But there is never a good moment to be dumping a disgraced prime minister.

They tell us he’s done well over Ukraine, and his critics can afford to admit it without worrying that this bright spot will blind us to his many flaws and failures. But were Johnson to choke on a canape at a not-party tomorrow, British support for Ukraine would continue, if only because MPs and the public would demand it. Would removing him somehow encourage Vladimir Putin? The Russian leader has invaded Ukraine and overseen war crimes with Johnson in office. How much worse will he be during a Tory leadership campaign?

Ah, but who will succeed him? There are 360 Conservative MPs in Parliament. If there isn’t one of them that would do a better job of being prime minister than Boris Johnson, we should have an election.

The one group of people in whose interests it surely is to keep Johnson in place is the Labour Party. Every day he stays in Number 10, laughing to the cameras at how silly it is that little people feel bound by laws and taxes and other Lilliputian ropes, is a good day for Keir Starmer.

Conservative MPs should take comfort that the idea of Johnson’s magic common touch turns out always to have been something of a myth. According to the essential study, The British General Election of 2019, Theresa May, with all her flaws, was more popular at every stage of the 2017 campaign than Johnson was at any point two and a half years later. The difference was made by the collapse in support for Jeremy Corbyn. There’s probably a lesson there about hanging onto a leader you know to be unfit, if only anyone could see what it was.

So, who could have guessed that Boris Johnson would turn out, once again, to be Boris Johnson? Conservative MPs didn’t need to guess because they always knew. In 2019, fearful that they would lose Brexit and have a Corbyn government, the Tories selected as a leader a man that most of them were aware had neither the character nor the ability nor frankly the interest to do the job. They knew who he was, and they knew that the risk was they would have to get rid of him in awkward circumstances.

Here we are. Do your job.