When Boris Johnson’s cabinet met by video link on Halloween weekend, as he rushed forward plans to announce an England-wide lockdown after they emerged in the press, Gavin Williamson gave colleagues a ticking off about leaks. The irony of Williamson’s lecture was not lost on others present. It was the education secretary who less than 18 months earlier had been sacked by Theresa May over the leak of sensitive discussions about the Chinese tech giant Huawei. Williamson protested his innocence; but in any case, when Johnson won the leadership he wiped the slate clean. Leaking from May’s deeply divided cabinet became so endemic that one minister said they learned to spot when a colleague made a particularly wordy intervention that appeared designed to find its way into the press. Ministers on either side of the Brexit divide were keen to ensure that whatever the outcome of cabinet discussions, their contribution to the argument was recorded for posterity. The then chief whip, Julian Smith – responsible for party discipline – later gave a BBC interview saying May’s cabinet had been the “the worst example of ill-discipline in cabinet in British political history”. The Johnson regime was meant to be different: when he wrote the foreword to a reworked ministerial code last August, he promised there would be “no leaking; no breach of collective responsibility”. And his aides Dominic Cummings and Lee Cain went about enforcing that diktat with zeal. They banned special advisers from accepting hospitality from journalists – with some reports even suggesting Cummings had a network of “spies” in popular Westminster bars and restaurants to spot who was lunching whom. Those accused of leaking were sometimes treated brutally – Sajid Javid’s aide Sonia Khan was summarily sacked by Cummings and marched out of Downing Street by police. Last month, the government paid between £50,000 and £100,000 to Khan to settle her claim of unfair dismissal, shortly before a five-day hearing for the case was due to begin. A former special adviser to Grant Shapps, Neil Tweedie, recently claimed in the Mail on Sunday that Cain had warned him, after a spate of well-informed stories about changes to travel restrictions appeared, that “if leaks carry on, we’ll start shooting people”. Tweedie, who denied he was the source of the leaks, was later fired. He was then rehired, after Cummings and Cain were forced out in what insiders say was a power-struggle with Johnson’s partner, Carrie Symonds, and the new Downing Street press secretary, Allegra Stratton. It remains to be seen whether this new No 10 regime will be more successful in stopping Tory tongues wagging. But they may find that like backbench rebellion, which has proved impossible to quell despite Johnson’s safe majority, leaking is a tough habit to break. Meanwhile, the House of Commons Speaker, Lindsay Hoyle, has repeatedly asked for updates on No 10’s investigation into the lockdown leak – but nothing has so far emerged.