The ruling comes after the FDA union brought a judicial review over the prime minister’s decision last year to overrule the findings of his then adviser on ministerial standards over the home secretary’s conduct.
An investigation by Sir Alex Allan, the independent adviser, found that “her approach on occasions has amounted to behaviour that can be described as bullying in terms of the impact felt by individuals”.
It concluded Ms Patel’s behaviour was in breach of the ministerial code “even if unintentionally”.
But in a move that resulted in Sir Alex’s resignation, Mr Johnson, the ultimate arbiter of the ministerial code, said the home secretary was “unaware” of the impact she had and he was “reassured” she was “sorry for inadvertently upsetting” individuals.
After “weighing up all the factors”, he concluded the code had not been breached.
In a hearing last month, lawyers for the FDA argued Mr Johnson “misinterpreted” the term “bullying” in the ministerial code when deciding if Ms Patel’s treatment of civil servants breached its standards. They alleged he made a “misdirection of law” in reaching his decision.
But delivering a ruling on Monday, Lord Justice Lewis concluded that the prime minister had not misdirected himself as to the provisions in the ministerial code when reaching his decision.
The judge, sitting with Ms Justice Steyn, said: “The question for this court is whether the prime minister proceeded on the basis that conduct would not fall within the description of bullying within paragraph 1.2 of the ministerial code if the person concerned was unaware of, or did not intend, the harm or offence caused.
“Reading the statement [made by Mr Johnson] as a whole, and in context, we do not consider that the prime minister misdirected himself in that way.”
Despite the case being dismissed, the FDA general secretary Dave Penman said the judgement was an “important step forward in the battle to ensure that ministers are held to account for their behaviour in the workplace”.
He added: “The court has also determined that while the prime minister is the ultimate arbiter of the code, this does not mean that he can give any interpretation he chooses of the words in it.
“This is critical, as the government argued in court that the prime minister could decide what the words in the code meant, uninfluenced by external standards or definitions of bullying.
“The court rejected this argument, and aligned bullying in the code with how it is understood in workplaces across the UK. There cannot be one rule for ministers and one rule for the rest of us when it comes to bullying and harassment, and this judgment confirms that the prime minister cannot simply make up whatever definitions or standards he chooses.”
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