Normally, a “three strikes and you’re out” rule would appeal to Priti Patel, as the home secretary is a hardliner on law and order. She will be rather less in favour of the maxim today, after allegations that she bullied civil servants in a third government department surfaced.

It was inevitable other officials would emerge from the Whitehall woodwork after last weekend’s dramatic resignation by Philip Rutnam as permanent secretary at the Home Office. There have since been claims that Patel also bullied civil servants at the Department for Work and Pensions (DfID) and the Department for International Development. She denies all the allegations.

One DfID official told me at the time that her attitude towards her staff was, “You’re all useless.” Another said: “She was interested in her own career; she wasn’t interested in the department.” Her officials felt she misled them over her infamous “holiday” to Israel, which forced her resignation because she had secret meetings with senior Israeli figures.

Boris Johnson knew all about the Israel controversy because he was foreign secretary at the time. (Patel privately blamed her downfall on leaks from Foreign Office officials). However, when it came to forming his cabinet last July, Patel ticked several boxes: he trusted her, having spent time with her on the Vote Leave battle bus in 2016; her appointment would boost diversity on two fronts; and she was hardline on crime, an issue on which Johnson believed the Tories had lost their way under Theresa May’s premiership.

As Patel clings on to her job by her fingernails, Johnson has an agonising dilemma. He would like to stand by her, but her continued presence will ensure more damaging headlines. Even in a less high-profile post, there is no guarantee that her alleged treatment of civil servants would change. More officials would likely feel emboldened to speak out. Johnson may eventually judge cutting her loose as the lesser of two evils: if Rutnam were then persuaded to drop his unfair dismissal claim, it might spare the government a highly embarrassing employment tribunal.

But if Johnson were to force her out, it would reflect badly on his own judgement in appointing her to such a big job in which she has looked out of her depth. Her media appearances have had to be rationed.

Characteristically, the feisty Patel is not going to go down without a fight. Her allies claim that sections of the civil service are trying to undermine the home secretary, and that “dark forces” are trying to influence the Cabinet Office inquiry into her conduct at the Home Office. This is yet another example of the Johnson government taking a leaf out of the Trump playbook, in an echo of the president’s equally ludicrous conspiracy theory about a “deep state” in Washington undermining his administration.

In politics, you reap what you sow. You cannot run a department of 35,000 civil servants, such as the Home Office, with three trusted special advisers. The Johnson government needs to put its Trump-like paranoia to one side and work with officials, the overwhelming majority of whom want to deliver for the government of the day, whatever its political hue.

After the latest allegations about her time at DfID, there are signs that support for Patel in her own party is waning. At lunchtime on Monday, Downing Street ruled out an inquiry into her behaviour. By 3.30pm, one had been announced. Some Tory backbenchers who loyally parroted lines from the whips in support of her in the Commons on Monday privately wonder if they did the right thing.

Ministers cannot claim to be determined to stamp out the bullying of parliamentary staff and yet remain judge and jury when such allegations are made against fellow ministers. Nor should the fate of a minister whose career hangs by a thread be decided on the basis of which side of the Brexit divide they were on.