THE Metropolitan Police is being sued over its refusal to investigate parties held on Downing Street during lockdown.

Good Law Project has previously threatened the London force with legal action over its failure to look into the mounting allegations.

The Met previously said it would not investigate reports of a slew of lockdown-busting parties held by the top levels of the Tory government “based on the absence of evidence and in line with our policy not to investigate retrospective breaches”.

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However, Good Law Project gave the Met two weeks to respond after publishing legal advice which suggested that those excuses could be unlawful.

Now, following revelations that Boris Johnson and his wife Carrie attended a party to which around 100 people were invited at the height of lockdown, the Met is being sued.

Good Law Project wrote on Twitter: “The Met seem to be operating a two-tier system, with one rule for those in power and one rule for everyone else. Enough. We're suing.”

Elsewhere, they added: “In what other crime would police decline to investigate because the suspect assured them no rules had been broken?

“It is not good enough for the Met to delegate their investigative duties to the press and civil servants. We don’t believe they would make such concessions for anyone else accused of breaking the law.”

The non-profit said they had instructed Bindmans LLP, and Danny Friedman QC and Adam Wagner are acting as counsel.

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The legal case focuses specifically on a party allegedly held on December 18, 2020.

Good Law Project added: "If we win, it could have a knock-on effect for all the parties held at Downing Street. Those in power broke the rules - repeatedly. They should face the same consequences as everyone else."

Jo Maugham, the non-profit's director, added: "You can have the rule of law, or you can defer to the powerful. But you can't have both.

“Cressida Dick's cat will know that multiple criminal offences were committed. It shames the Met, and ultimately all of us, that she refuses to investigate."

The National: Dame Cressida Dick

Asked in December if the Met would investigate reports of lockdown breaches at No 10, Cressida Dick (above), the force’s head, said: “The answer is no, we are not investigating that and I can’t really comment on what did or didn’t happen there.”

On Monday, ITV published an email sent by Boris Johnson’s principal private secretary, Martin Reynolds, inviting around 100 people to “bring your own booze” to a party at No 10 on May 20, 2020.

Rules at the time allowed only two people from different households to meet outside, at a distance of two metres.

Responding to the publication, a spokesperson for Scotland Yard said: “The Metropolitan Police Service is aware of widespread reporting relating to alleged breaches of the Health Protection Regulations at Downing Street on May 20, 2020 and is in contact with the Cabinet Office.”

The cabinet secretary, Simon Case, had been tasked with investigating the parties held by the government in breach of lockdown rules. However, he stepped down to be replaced by Sue Gray after reports emerged that he had seen parties hosted in his own office.