There is a grim inevitability to the trickle of round-robin letters from scientists who feel aggrieved at the government’s handling of the Covid-19 crisis. Right from the beginning, the Prime Minister gave scientific advisers a very public platform at the heart of government. He realised that if it became necessary to impose the most severe restrictions on personal freedom any government has had to introduce in peacetime, it would help if the public could see policy was being shaped by experts who understood the threat.