THE UK’s deputy prime minister, Dominic Raab, is being investigated over formal complaints spanning his behaviour at three separate government departments.

Raab was already being formally investigated after complaints were lodged about his behaviour as foreign secretary and justice secretary. He is now having his time as Brexit secretary probed as well.

At Raab's request, Prime Minister Rishi Sunak appointed top employment barrister Adam Tolley KC to privately probe two complaints and report his findings directly. The remit of the investigation has now been expanded to include the third, Downing Street has confirmed.

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“I can confirm that the Prime Minister has now asked the investigator to add a further formal complaint relating to conduct at the Department for Exiting the European Union and to establish the facts in line with the existing terms of reference,” a spokesperson said.

No 10 insisted Raab still has Sunak’s confidence, noting that the third formal complaint was received by the Cabinet Office on November 23.

The BBC reported that the justice department – which Raab led under Boris Johnson from September 2021 and now leads again under Rishi Sunak (below) – had been “inundated” with complaints about the top Tory’s behaviour.

The National: Rishi Sunak

Further complaints from multiple senior officials who worked closely with the deputy prime minister are being prepared, according to various reports.

One source told the Mirror that civil servants were "scarred psychologically from having to deal with him and they are terrified to make a complaint".

Raab has insisted that he always adhered to the ministerial code and “behaved professionally”.

He told the BBC he looked “forward to dealing with [the complaints probe] fully and transparently rather than dealing with anonymous comments in the media”.

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Raab was foreign secretary from July 2019 until being moved to the justice brief in September 2021, and was briefly Brexit secretary from July to November 2018.

Liberal Democrat chief whip Wendy Chamberlain demanded an investigation after it also emerged that Raab had used his personal email account for government business.

Allies of the Justice Secretary insisted there were no breaches of the ministerial code because he copied in an appropriate government email address when required by the guidance.

They also argued he was using his personal account just to approve tweets and quotes with his team at short notice.

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But Chamberlain said: “The public deserve answers, not more cover-ups.

“The deputy prime minister cannot be relaxed about national security especially at a time when Britain’s enemies are stepping up their cyber attacks.

“It is only right and proper the Cabinet Office investigate these reports and determine immediately if overseas enemies could have seen national secrets sent by Dominic Raab.”

But Downing Street backed Raab and rejected suggestions the investigation would be a whitewash, despite Sunak’s ability to reject its findings.

“It’s a long-standing convention that the prime minister of the day is the arbiter of the [ministerial] code and the final decision-maker on these sorts of issues,” the Prime Minister’s official spokesperson said.

“The investigator looking into this is highly experienced and has a suitable background, and is being given access to whatever they need to conduct a thorough and swift investigation.”

Deputy Labour leader Angela Rayner said: “There must be no hint of a whitewash when it comes to the slew of serious allegations the Deputy Prime Minister now faces.

“The scope of this investigation must immediately be expanded to enable proactive investigation of Dominic Raab’s behaviour during his time as a minister, including so-called expressions of concern, informal complaints and the concerning testimony of his own former permanent secretary.”