Why it matters No 10's press chief was at the Downing Street party

There have already been many twists and turns in the saga of the Downing Street party, or "gathering" as government ministers have now taken to calling it.

There's been a resignation already, leaked footage, questions in Parliament and now a formal investigation.

Why therefore does it matter that we know the identity of one of those who was there?

Well it's understood that Jack Doyle, the current Downing Street director of communications was, and he made a speech to as many as 30 people in the press team and handed out a series of awards.

We've been told that it was a weekly occurrence for him to thank staff each Friday night.

But on that evening of 18 December last year he gave out multiple, light-hearted awards and we've been told there was food, drink, and party games. We've also been told the event went on past midnight.

There is now an official investigation into what happened. And at the heart of government there is no desire for other staff to quit or be forced out before it has run its course.

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There is still a determination to challenge the assertion that the gathering of several dozen people was really a party, rather than a permitted get-together of work colleagues.

There is no question that the press team in No 10 work hard and put in extremely long hours. At that point in time they were dealing with the pandemic and the final crescendo of the Brexit talks too.

But other sources in Westminster are now questioning whether it is possible for Mr Doyle to stay in his job.

In part that's because one of the problems this week for No 10 has been their efforts to deny and explain what did or didn't happen.

Ministers, and the prime minister himself have been stuck in the Kafka-esque position of saying that they are sure no rules were broken, but they also don't know what went on.

If they don't know what happened, how can they be sure that nothing went wrong?

And if multiple sources have said there was a gathering of several dozen people, and people who were not on the Downing Street payroll were invited, how can that have been just a few work drinks at the desk in a Covid-secure office?

Mr Doyle, well liked by his colleagues, is - as director of communications - in charge of the government's messaging.

This week that message has misfired, which makes his confirmed attendance a very big problem.

And as government spinners over the years have often found, there is one fundamental error which they cannot make. That's to become part of the story themselves, an uncomfortable position that Boris Johnson's press chief now finds himself in.

For governments to function, the public has to be able to put their faith in the message they are hearing day to day.

When that falters, as it has this last few torrid days, that can be costly for a government.

Right now that's a price that the prime minister can ill afford.