Boris Johnson is facing legal action over his award of a peerage to a wealthy Tory backer against the advice of the official House of Lords watchdog.
Electoral Commission records show Peter Cruddas, a former Conservative Party treasurer, gave the Tories a further £500,000 just three days after taking up his seat in the upper chamber last February.
The City financier – who has given the party more than £3 million since 2010 – has strongly denied there was any link between the donation and his receipt of a life peerage.
However the Good Law Project – which has brought a series of judicial review cases against the Government over the award of contracts during the pandemic – has said it intends to challenge his appointment in the courts.
The legal campaign group’s director Jo Maugham said it was unprecedented for the Prime Minister to press ahead with the nomination after objections were raised by the independent House of Lords Appointments Commission.
The body – which vets new peerages – raised “historic concerns” over allegations that Lord Cruddas had offered access to then-prime minister David Cameron in exchange for donations to the party.
Mr Maugham said the Good Law Project’s lawyers had advised there was “apparent bias” in Mr Johnson’s decision to continue with his appointment regardless.
He said: “The independent watchdog didn’t think Peter Cruddas should be given a peerage. But Boris Johnson ignored their advice and appointed him anyway.
“Just three days after he entered the Lords, he gave the Conservatives half a million quid. I don’t think this is lawful.
“I think a fair-minded observer, presented with the facts, would conclude there was a real possibility or danger of bias in the Prime Minister’s decision-making.”
The campaign group has set out its case in a pre-action protocol letter sent to the Prime Minister.
A Downing Street spokesman said: “All individuals are nominated in recognition of their contribution to society and their public and political service.
“Lord Cruddas has a broad range of experiences and insights across the charitable, business and political sectors which allow him to make a hugely valuable contribution to the work of the Lords.”