Women died as a result of domestic abuse during the first lockdown partly because of a lack of diversity in No 10, a former senior civil servant has said, criticising Boris Johnson for failing to challenge “violent and misogynistic language” used about her. Helen MacNamara was giving evidence to the Covid-19 inquiry a day after an appearance by Dominic Cummings, Johnson’s former top aide, who was asked about messages in which he said No 10 was “dodging stilettos from that cunt”. MacNamara, who served as deputy cabinet secretary and was one of the country’s highest ranking female officials, told the inquiry: “The way in which it was considered appropriate to describe what should happen to me, yes, as a woman, but, yes, as a civil servant, it is disappointing to me that the prime minister didn’t pick him up on the use of some of that violent and misogynistic language.” When asked what she thought about Cummings’ WhatsApp messages, and Johnson’s apparent failure to act, she replied: “It is just miles away from what is right or proper or decent, or what the country deserves.” In the latest inquiry hearing laying bare the extent of conflict and dysfunction inside Downing Street during the pandemic, MacNamara spoke of a “toxic environment” where female civil servants found they had “become invisible overnight”. They were spoken over or ignored, she said, while meetings in Downing Street were dominated by men. An email entered into evidence from MacNamara showed she sought to highlight consequences of a lack of gender diversity among decision makers, starting with the lack of provision for domestic abuse victims during the first lockdown. “It is very difficult to draw any conclusion other than women have died as a result of this,” the email said. Asked about the email at the inquiry, she said: “People don’t want to think about these things, so you don’t want to think that awful things happen to children and partners and parents in their own home.” She said concerns were raised on a number of occasions about personal protective equipment (PPE) not being designed for women’s bodies. Johnson was said to have raised the issue with the former chief executive of the NHS in England, Simon Stevens, who said there was no problem, according to NacNamara, but the then-deputy chief of staff, Cleo Watson, had emailed her later: “Astonishing. 2 weeks later and finally raised in one of these meetings.” Also appearing at the inquiry, a key figure who headed the government’s so-called nudge unit said the Johnson administration’s over-confidence in UK science delayed considering other approaches that could tackle the virus. Prof David Halpern, a psychologist and founding director of No 10’s behavioural insights team, said there was “a touch of hubris that we knew better and we would do better, alongside criticisms of how badly other countries were doing”. There was a sense “we were lucky almost to have the best team”, Halpern told the inquiry, that brought “a lacuna with it of over-confidence” and “less openness” to other approaches. He also criticised Johnson’s government’s “stay alert” messaging. “It tells you to worry and doesn’t tell you what to do – the worst combination,” he said. Along with her criticism of Johnson and Cummings, there were also accusations from MacNamara about the performance of the then health secretary, Matt Hancock. She said he had routinely claimed in meetings that certain things were happening or were being delivered, but it had transpired that they were not. When asked by Andrew O’Connor KC, for the inquiry, if Hancock was “regularly telling people things that they later discovered were not true”, she replied: “Yes.” Until now, MacNamara has been best known to the public for her role in Partygate, having apologised in April last year for her “error of judgment” after being fined by police for attending a party in the Cabinet Office during lockdown. She provided a karaoke machine for the event, which is understood to have been one of the most raucous gatherings under investigation. She told the inquiry that she had “profound regret” about the situation, but had to be reminded by O’Connor that she was at Downing Street during one of the events that had led to fines after she claimed: “I definitely wasn’t partying in No 10.” She said she had been worried about the “kind of culture” that staff were working in and the need for them to have space to spend time together. “My profound regret is for the damage that has been caused to so many people because of it, as well as just the mortifying experience of seeing what that looks like, and how rightly offended everybody is, in retrospect.” MacNamara suggested rules had been being broken on a daily basis just in the conduct of government business. There was “one [cabinet] meeting where we absolutely adhered to the guidance to the letter and everybody moaned about it and tried to change repeatedly,” she said. “So, I know how exceptional it was to really, really, really properly follow the guidance. I think that, in retrospect, obviously, all sorts of things were wrong.”