Ex-Tory mayoral hopeful Shaun Bailey will not be investigated by City Hall's standards watchdog, despite attending a rule-breaking Christmas party.
An extraordinary image, obtained by the Mirror, showed Mr Bailey at a "raucous" bash at the party's Westminster HQ in December 2020, when London was living under Tier 2 rules.
Mr Bailey "apologised unreservedly" when the picture emerged of 24 people crammed in together, with some raising glasses of wine while posing near a catered buffet.
Labour complained to the London Assembly's monitoring officer last month over the party, which flouted a ban on mixing between households in the capital at the time, according to MyLondon.
At least four members of Bailey's team were formally disciplined.
Leonie Cooper, Labour's acting leader on the London Assembly, wrote to City Hall's standards watchdog over his actions, saying: "Assembly Member Bailey’s attendance at the party in question is in direct contravention of the Covid rules at that time.
"That fact, combined with his evasion of any questions surrounding this party and the notion that this flagrant flouting of the law coincided with a time in which Londoners were making considerable sacrifices to keep one another safe, calls into question whether Assembly Member Bailey is in contravention with the Greater London Authority’s (GLA) code of conduct."
City Hall rules say Assembly Members must not conduct themselves "in a manner which could reasonably be regarded as bringing your office or authority into disrepute".
But in a new ruling, seen by MyLondon, the monitoring officer said Mr Bailey was attending in his capacity as a mayoral candidate, not an Assembly Member (AM).
She wrote: "There is no other information available to me to suggest that the event was part of the business of the Authority, nor the business of the London Assembly, or in connection with his role as an Assembly Member."
Mr Bailey has quit as chair of the London Assembly's economy and policing committees, following anger over the party.
A spokesperson for the Greater London Authority, said: "The GLA's Monitoring Officer has conducted an initial assessment of the complaints.
"She has concluded that no action should be taken as the Member in question attended the event in his capacity as a mayoral candidate, not as an Assembly Member, and cannot therefore be in breach of the Authority’s Code of Conduct."
In the first meeting at the new City Hall in Newham on Thursday, assembly members passed a motion criticising politicians who refuse to follow the Covid rules.
Conservative members abstained from voting.
Mr Bailey, who is paid £58,000 a year as an AM, remained silent throughout the four hours, refusing to comment or restate his apology.
London Mayor Sadiq Khan said his apologies had been "mealy mouthed" and called for him to quit.
"His resignation as an assembly member must surely now be an inevitability," he said. "Londoners deserve much better representatives than that."
Mr Bailey apologised for attending the gathering but initially his team claimed he left early - a claim disputed after the Mirror found he stayed until at least 10pm.
The City Hall Conservative party said it would not be commenting further.
Previously, a GLA Conservative spokesman said: "He does not want an unauthorised social gathering involving some former members of the London mayoral campaign team last December to distract from the Committee's important work holding the Mayor of London to account."
