Militarising the border with France and abolishing the BBC licence fee may seem an extreme way to win back estranged backbench MPs, but the Prime Minister is in dire straits.

The heaviest burden is therefore on Sue Gray, the second permanent secretary at the Cabinet Office. She has been given the unenviable task of providing an objective assessment of whether lockdown or other rules were broken when Downing Street partied over the past 18 months and who may have been to blame.