The new prime minister is expected to take the hugely controversial step of inviting the head of the Vote Leave campaign – and the brains behind the notorious “£350m-a-week for the NHS” claim – into No 10.
The move was immediately condemned by Sarah Wollaston, a former Conservative, now Independent, MP as “shameful”.
“If true, would be an appalling error of judgement to appoint someone who has been in contempt of parliament,” Ms Wollaston tweeted.
Mr Cummings is hugely respected by most Brexiteers as the inspiration behind the 2016 referendum campaign that delivered the vote to pull out of the EU against all the odds.
Boris Johnson's cabinet: Who's in and who's out
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But, earlier this year, MPs passed a formal motion condemning him for his “significant interference” in the work of a Commons committee probe into “fake news”.
Mr Cummings was also the architect of the “take back control” slogan, credited with helping to persuade the British public of the case for Brexit.
As Vote Leave’s director, he made a show of refusing to work with Nigel Farage and Arron Banks – while admitting his campaign relied on their harsh anti-immigration messages.
Crucially, the cash was used to pay data firm Aggregate IQ and – a whistleblower and an Oxford professor argue – potentially enabled it to precisely target enough voters on social media to have swayed the Brexit result.
Virendra Sharma, a Labour supporter of the anti-Brexit Best for Britain campaign, linked the appointment to Mr Johnson’s threat “to suspend parliament to force through a damaging no deal”.
“Cummings is a bully who only pays lip service to democracy,” Mr Sharma said, “he doesn’t really care.”
Since the referendum, Mr Cummings has described Brexit as a “train wreck”, said triggering Article 50 too early was like “putting a gun in your mouth and pulling the trigger” and branded David Davis, the former Brexit secretary, “thick as mince and lazy as a toad”.
However, in a further sign of tensions to come, he also turned on the hard-Brexit backing European Research Group for its Brexit blunders.
“You were useful idiots for Remain during the campaign and with every piece of bullshit from Bill Cash et al you have helped only Remain for three years,” he wrote.
“So many of you guys were too busy shooting or skiing or chasing girls to do any actual work. You should be treated like a metastasising tumour and excised from the UK body politic.”
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