The Sue Gray report has ruffled feathers in Westminster and around the UK today after its damning conclusion that the Partygate scandal "fell well short" of standards expected in No. 10.
Many have anticipated the outcome of the report from the senior civil servant for several months after its release was delayed during a Met Police investigation into parties in Downing Street.
While Miss Gray, who joined the civil service straight out of school, is enormously respected in Whitehall, she was actually the second choice to investigate Partygate - after top civil servant Simon Case had to step down.
Just a week after Mr Case was initially earmarked to write the report, it was revealed he had been present at a private gathering in his own office that breached coronavirus restrictions.
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Mr Case was not fined in the Met Police's investigation into gatherings at 10 Downing Street - but the findings of the Gray Report put much of the responsibility for the partying culture in Whitehall at the door of senior leaders.
In her conclusion, Miss Gray writes: "The senior leadership at the centre, both political and official, must bear responsibility for this culture."
Despite this scathing observation, Simon Case is not expected to resign from his role as Head of the Civil Service.
The dad-of-three and Cambridge graduate has held several high-ranking positions in Whitehall throughout his career, including Principal Private Secretary (PPS) to the Prime Minister serving both David Cameron and Theresa May.
After first joining the civil service in 2006, the Bristolian worked in the Ministry of Defence before moving to the Northern Ireland Office and the Cabinet Office.
He also worked as Head of the Olympic Secretariat which oversaw the delivery of the London 2012 Olympics.
After Brexit, Case was tasked with solving the Irish border issue in negotiations in his role as Director General for Northern Ireland and Ireland.
In 2018 he even did a stint working as PPS to Prince William - being appointed shortly after Harry and Meghan's wedding.
Case, who is married to the chief finance officer for Expedia and Hotels.com Elizabeth Kistruck, was also asked to give evidence in the Greensill inquiry.
The inquiry investigated lobbying activities in government on behalf of finance company Greensill Capital - run by businessman Lex Greensill.
One major focus of the inquiry was Case's former boss and ex-Prime Minister David Cameron.
