Peston: Partygate fines confirm Boris Johnson misled the Commons

The significance of today's announcement by the Met Police that there will be 20 fines of individuals who unlawfully attended parties in Downing Street and the Cabinet Office is that it confirms the prime minister misled the House of Commons on December 8.

On that date he told Sir Keir Starmer, Labour's leader: "I have been repeatedly assured that the rules were not broken. I repeat that I have been repeatedly assured since these allegations emerged that there was no party and that no Covid rules were broken."

We now know there were lots of parties, and the Covid-19 rules that banned them at the time - drafted by the government on the orders of Boris Johnson - were breached.

What we don't know, of course, is whether the prime minister knowingly misled the House of Commons. If he knew he was lying, that would mean that under the prevailing conventions he would have to resign.

But if he himself was misled by his own officials, and then misled the House of Commons, he would still need to come back to Parliament and correct the record - which in itself would be embarrassing for him.

For what it's worth, there is no indication which officials - or indeed politicians - will receive the so-called fixed penalty notices that trigger the fines.

And it's completely possible we won't ever know the names of all or any of them. Because they are likely to be informed privately of their fines by letter, in coming days, and are under no obligation to tell anyone about them. You can decide whether it's appropriate that those at the heart of government who broke Covid laws never need reveal their respective breaches.

There is just one exception to the cloak of secrecy around the fines. Downing Street has said the PM will disclose if he is fined.

And at the theoretical juncture, his MPs will have to decide whether he would remain fit and proper to lead them and us.