The main cause of the Metropolitan Police's disastrous investigation into fabricated claims of a VIP paedophile ring in Westminster was "poor judgement and a failure to accurately evaluate known facts", a damning report has said.
Former High Court judge Sir Richard Henriques also said a "major contributing factor was the culture that 'victims' must be believed" in his findings, more of which were published by the Metropolitan force today after coming under pressure to be open and transparent.
Sir Richard, a retired Lancashire-based judge and barrister, was called in after 16-month Operation Midland ended in 2016 without a single arrest.
It saw the homes of D-Day veteran Lord Bramall; Lady Diana Brittan, the widow of former home secretary Leon Brittan; and former Tory MP Harvey Proctor raided on the basis of false claims made by fantasist Carl Beech.
Beech, previously known only as Nick, is serving an 18-year jail term for fabricating a series of claims of rape, torture and murder by innocent, well-known names from the military, security services and politics.
The report said: "Whilst the responsible officers assert that they kept an open mind, several failures can only be explained by an unwarranted and disproportionate belief in 'Nick's' credibility.
"The most significant error in this investigation was the decision to apply for search warrants coupled with formulating inaccurate statements which were placed before the district judge.
"But for that decision, this investigation may well have been completed without the dreadful adverse consequences I have described."
The officer in charge of Operation Midland Steve Rodhouse has apologised for the "distress" caused as a result, saying the report shows there are "clearly lessons to be learned for future investigations".
He said: "In hindsight I can see I did not ensure that we got the balance right" between a "determination to maintain confidence" and the police's "duty to robustly test the allegations being made".
Deputy Commissioner Sir Stephen House: "The Met is determined to learn lessons from Sir Richard's review to improve our response to similar situations in the future.
"The Met and the officers involved cooperated fully with Sir Richard.
"Mistakes were made in Operation Midland and we have apologised for those. We apologise for them again today.
"However, we do not agree with everything Sir Richard wrote in his report or indeed all of his recent statements regarding further investigations into the actions of officers."
Mr Proctor called for the force's commissioner Cressida Dick to "consider her position", saying: "She showed no leadership or professional ability to insist on investigation into Beech himself."
He accused her of failing to amend previously inaccurate statements on the credibility of Beech's allegations, adding: "Her inaction was irresponsible and immoral and she should now consider her position."
While Daniel Janner, the son of the late Labour MP Lord Janner who was one of Beech's victims, accused deputy Labour leader Tom Watson - who raised the matter in Parliament after speaking to Beech - of being "partially responsible", claiming he "applied pressure on the police and should hang his head in shame and resign".
Mr Watson said the review contained "multiple inaccuracies" about him and said it did not make clear letters from him were received by police after they had already interviewed Lord Brittan.
In a statement he said it "cannot be argued that it was pressure from me that led to Lord Brittan being interviewed".
He added: "I have always said that it wasn't my place to judge whether sexual abuse allegations were true or false - that was for the police."
Before the report was published Ben Emmerson QC, the lead counsel to the Independent Inquiry into Child Sexual Abuse, claimed he warned Scotland Yard of Beech's "bogus allegations" months before officers shut down the investigation.
He said he interviewed Beech in 2015 and claims to have told senior police officers on September 30 that year not to believe his claims of rape and torture, adding: "They had a ring of outlandish fabrication about them."