Sue Gray has blamed “senior leadership” at the top of government for allowing lockdown-busting parties to take place in Downing Street and Whitehall.
In an implicit criticism of Boris Johnson, she said those in charge “at the centre, both political and official, must bear responsibility” for what went on.
She also said the behaviour of those involved “fell well short” of the standards the public expected of those running the country.
The 37-page report into 16 gatherings in Downing Street and Whitehall was finally handed to the prime minister at around 10am this morning.
It followed the conclusion of Operation Hillman, the Metropolitan Police’s partygate investigation.
The force issued 126 fixed penalty notices to 83 people, including the prime minister, his wife Carrie and the chancellor, Rishi Sunak.
However, despite attending several other gatherings investigated as part of the probe, Johnson received no more fines.
In her report, Gray said: “The events that I investigated were attended by leaders in government. Many of these events should not have been allowed to happen.
“It is also the case that some of the more junior civil servants believed that their involvement in some of these events was permitted given the attendance of senior leaders.
“The senior leadership at the centre, both political and official, must bear responsibility for this culture.”
The report goes on: “Many will be dismayed that behaviour of this kind took place on this scale at the heart of Government. The public have a right to expect the very highest standards of behaviour in such places and clearly what happened fell well short of this.
“It is my firm belief, however, that these events did not reflect the prevailing culture in Government and the Civil Service at the time. Many thousands of people up and down the country worked tirelessly to deliver in unprecedented times.”
The report also contains photographs from the notorious surprise birthday party for the PM which led to his partygate fine.
In one, Johnson is shown raising a can of beer while Cabinet Secretary Simon Case laughs on the other side of a table with packets of sandwiches and drinks on it.
Other photographs also show the prime minister drinking at a Number 10 leaving party for his former director of communications, Lee Cain.
Gray’s report also tells of security and cleaning staff in 10 Downing Street being subjected to “unacceptable” treatment by officials.
“I found that some staff had witnessed or been subjected to behaviours at work which they had felt concerned about but at times felt unable to raise properly, the report said. “I was made aware of multiple examples of a lack of respect and poor treatment of security and cleaning staff. This was unacceptable.”
The PM is expected to issue another apology for the goings-on in 10 Downing Street in a Commons statement at 12.30pm.
He is expected to tell MPs: “I commissioned this report to set the record straight and allow us all to move on. I accept full responsibility for my failings. I am humbled by the whole experience. We have learned our lesson.”
Johnson will then address the country at a televised press conference at 3.30pm, before appearing before the Tory backbench 1922 committee at around 5pm.
The Gray report’s damning findings could lead to more Tory MPs submitting letters of no confidence in Johnson to Graham Brady, the 1922 committee chair. At least 54 are needed to trigger a confidence vote.
One backbench rebel told HuffPost UK: “It feels like there’ll be more letters now.”
Prior to the report’s publication, the BBC’s Panorama revealed more details of what went on inside Number 10 during lockdown.
Downing Street insiders told how Johnson would regularly attend drinking sessions, “wine time Fridays” were a weekly occurrence and how a security guard was mocked for trying to break up one gathering.
In an attempt to move on from the partygate saga, Sunak is expected to finally unveil the government’s plan to tackle the cost of living crisis, including a windfall tax on the bumper profits being enjoyed by the oil and gas companies, tomorrow.
A Labour source told HuffPost UK: “Boris Johnson’s pathetic last roll of the dice is to steal a Labour policy he’s been ruling out for five months. Sheer desperation.”