oh my god. The PM is stopping the medics from answering about Cummings.

It's in many ways bizarre that the Chief medical officer and chief scientific adviser don't have their own separate press conference to ensure their independence from the PM.
@BorisJohnson just trashed his own press conference.

Why don't the medics actually say something? Their indpendence is being totally flamed by the PM.

The fact is that whenever Whitty and Vallance are next on their own - away from the PM - they will asked about Cummings or Cummings-style breaches.
He can't chaperone them 24/7.
And if they refuse to comment at all, their independence really will be even more undermined.

Such an extraordinary own goal by Johnson. It's perfectly possible Whitty and Vallance would have said they didn't want to talk about individuals. But this will fuel the suspicion he knows they are unhappy at Cummings' conduct on public health messaging.

Whitty and Vallance both make clear their unease at getting dragged into 'politics'. But they must know the public health messaging problems revealed by opinion polls of recent days.