Robert Peston: Will the probe into 'Covid-rule-breaking' Downing Street parties be a 'Gray wash'?

As you may have noticed, the report into Downing Street's party culture was not published before Christmas as originally intended - because a bunch of additional gatherings were added to the scrutiny list, and Cabinet Secretary Simon Case recused himself from running the investigation.

As the senior official in Downing Street and Number 10, Case is technically responsible for what goes on there, and Case couldn't be seen to be marking his own homework (I made this point a week ago, as you may recall).

Instead the probe is now being run by the government's erstwhile propriety and ethics enforcer, the second permanent secretary at the Cabinet Office, Sue Gray.

She is still interviewing officials who attended the assorted parties. I am told by government sources that her report will therefore not be published this week and probably not next week either.

"The report will take two days to write after completion of interviews", said a source. "But the plan is to publish it in January if at all possible".

I am told very few party-going officials are likely to be named and personally criticised in the report.

Anyone likely to face sanction or even the sack for allegedly flouting social distancing and lockdown rules is being given representation and advice according to normal civil service procedures.

What is not clear is whether the prime minister will see and sign off the report before publication - though when Case was in charge of the probe, officials told me his review was being carried out on behalf of the PM, so that the PM could decide whether any heads should roll.

One official said to me that under the cover of broadening the scope of the review, a process has been created that will criticise cultural failures in Downing Street, but will probably shield any particular official or politician from personal responsibility for apparent rule breaches. This lessens the probability of dismissals or serious sanctions. An insider said to me: "it looks like a Gray wash".