“Alexander Boris de Pfeffel Johnson. You have paid your £50 fixed penalty notice and it is now the duty of this court of public opinion to pass sentence. You are an habitual chancer who accepts getting caught as an occupational hazard and presumably accepts punishment in the same casual manner … I sentence you

to …”

Porridge, with apologies to Dick Clements and Ian La Frenais

Sentence you to, well, what exactly? What is a suitable punishment for being the first serving British Prime Minister to be fined for breaking a law he set?

Somehow, a £50 fixed penalty notice, plus one for the missus and another for the Chancellor next door, does not quite measure up to the importance of the event.

Fifty quid will only get you half a dozen bottles of the cheapest plonk, a yard or two of golden wallpaper, or one of the Chancellor’s designer flip-flops. It is barely worth the bother of collecting. Still, it is important that the law should be seen to be upheld and all that.

The Prime Minister’s statement on Tuesday, after the fines were made public, showed he is still having trouble with the S-word (what is the problem with “sorry”: is it some terrible U, non-U faux pas like saying toilet instead of loo?). Instead he offered “a full apology” even while wriggling on the end of the hook. It did not occur to him, for example, that he might have breached the rules in attending his birthday party. “But of course, the police have found otherwise and I fully respect the outcome of their investigation.” Which is big of him.

The statement ended in typically cod Churchillian fashion with Mr Johnson burbling about fulfilling his duty to the British people, levelling up, defeating Putin, emptying the dishwasher more often, and so on. With one bound, one statement, he was free. But for how long and to what cost?

In terms of punishment, that six-hour silence from Rishi Sunak must have stung. How the Prime Minister must have wondered what was going on next door, his aides frantically pressing glasses to the wall. Had the Chancellor resigned on principle the pressure on his boss to do the same would have been unbearable, even for Mr Johnson, a man who does not “do” embarrassment the way Blair’s Number 10 did not do God. Eventually, the Chancellor too accepted the fine and apologised. He even said the S-word.

Now the Prime Minister and the Chancellor are locked together in a grisly embrace, the Anton du Beke and Ann Widdecombe of British politics. Both guilty of the same misdeed, they stand or fall together.

Not that Mr Sunak had much of a chance of becoming Prime Minister after last week’s tax debacle. Why it took six hours to realise this is a mystery, one which ought to worry the Prime Minister. If Mr Sunak could agonise for so long over whether he was still in with a shot at Number 10 he could entertain similar hopes again, particularly if the next few weeks do not play out as Mr Johnson hopes.

Much depends on timing, which has so far paid off for the Prime Minister. It is the Easter recess, few Tory MPs are around. In any case, most of them have decided that Mr Johnson has far more important things to be getting on with than resigning because he misled parliament.

Even the previously implacable Douglas Ross, leader of the Scottish Conservatives, has unblown his whistle and withdrawn that red card of his. He still shares the public’s “anger and fury” over Partygate, mind you, so that is something. But he is a bigger picture kind of politician is Mr Ross, believing a lengthy leadership contest to be unwise at a time of international crisis. Who knew Scottish politics had such a Charlemagne in its midst.

Still on timing, there is the matter of how long Mr Johnson was at the party he did not know was a party. Just nine minutes, his supporters protest. Oddly specific, don't you think? Meanwhile, the birthday cake, the one that supposedly ambushed him, lay untouched within a Tupperware container while he munched on salad. Dear God, hasn’t the man suffered enough?

Meanwhile, his wife was at the party for under five minutes, and poor Mr Sunak was there because he was due to attend a Covid strategy meeting in the same room. The irony, the injustice, of it all.

But now it is all out there, fines have been paid, apologies made, and we are all meant to move on. Yet there could be more fixed penalty notices heading the Prime Minister’s way. How many would constitute a resigning matter?

Also lurking in the print queue is the Sue Gray report, its publication put on hold till the police had finished their business. It could be months yet, or it could surface next week. Might Mr Johnson resign then, or are we to take it that the payment of a £50 fine has bought the Prime Minister an all-encompassing “get out of jail free” card?

The UK Government has made a cynical calculation and come to the conclusion that voters have moved on from Partygate, that they are far more worried about their heating bills and paying the mortgage than cheese and wine parties. The horrors of Ukraine are another reason to sober up about a few get-togethers in Downing Street.

I am not sure that reasoning will hold good for long. Many are still furious at Mr Johnson, and his rules, for depriving them of moments with loved ones that they can never get back. The worst outcome for the Government is that Partygate drifts on, a fine here, a revelation there, until it begins to build the same momentum it had just before Russia invaded Ukraine. Even the MPs’ expenses scandal looked survivable at first.

Disillusionment with politicians is like damp. You can cover it up with wallpaper, open the windows to let the stink escape for a while, but the rot is still there, and in the Conservatives' case it is spreading.

Mr Johnson has often been lucky in his career, but the odds are that there will be a reckoning at some point, a totalling up of the good deeds and the bad. It will take a lot to make up for “first serving Prime Minister to break the law” in the debit column. Mr Johnson will have his place in history; just not the one he desires.