Why Dominic Cummings insists he does not need to quit, writes Robert Peston

Dominic Cummings isn't resigning.

Or at least not by choice.

That much is crystal clear from Number 10's statement that "Mr Cummings believes he behaved reasonably and legally".

But it is striking that there is no endorsement from Boris Johnson or the government that it was appropriate to drive 250 miles with a spouse who had Covid-19 symptoms rather than quarantining for 14 days in their London home.

So the debate about whether he should quit will rage for a bit. It seems to me the competing arguments are these.

His defence is that he was doing what all parents would do, which is trying to protect his four-year-old child in the event both parents fell seriously ill with Covid-19 by going to a place where his sister could look after his son, should the worst happen.

He drove before the symptoms laid him low, and when he got there he stayed in a house separate from his parents, who are in their seventies, and separate from his sister.

And my goodness, according to the account of how ill he then became given by his spouse Mary Wakefield in the Spectator a month ago he really did then become dangerously unwell.

The charge against him is that he risked transmitting the dreadful virus to another part of the country by driving so long and far, because Mary Wakefield was already conspicuously unwell with Covid-19 symptoms.

However, Cummings says that the police have not - as reported - talked to either him or any member of his family about whether he breached rules with his escape from north London to the north east.

That said, the question of police involvement always looked a slight red herring to me. The bigger issue is all about the tension between public and private responsibilities for powerful officials such as Cummings.

Many of us would understand why he puts family first and why he is comfortable with what he did, especially since much of his self-image is of someone who is a permanent foreigner in London.

But millions of people trapped indoors for weeks will struggle with the idea that he didn't breach the spirit of quarantine and lockdown rules that he did so much to write.