A former MP falsely accused of being part of a VIP paedophile ring has branded a review of how detectives handled the claims as “a whitewash”.
The police watchdog identified “organisational failings” but cleared five detectives of wrongdoing.
Harvey Proctor said its report was “a pathetic attempt to excuse the police for their mistakes” and “negligence”.
The Independent Office for Police Conduct (IOPC) said its work was “thorough” and “detailed”.
In its report, published on Monday, the IOPC found no evidence of misconduct but said the investigation “revealed gaps and shortcomings where there is room for improvement to reduce the risk of future failings”.
It made 16 recommendations to improve policing practice, including on search warrants and ensuring allegations are investigated objectively.
No officers were prosecuted or disciplined for their part in Scotland Yard’s £2.5 million Operation Midland, which investigated bogus claims made by Carl Beech, previously known as “Nick”.
Beech, 51, from Gloucester, was jailed for 18 years for his false accusations.
The claims prompted searches of the homes of three prominent people – Mr Proctor, D-Day veteran Lord Bramall and Lady Diana Brittan, the widow of former home secretary Leon Brittan.
In a 2016 report into Operation Midland, retired High Court judge Sir Richard Henriques found the searches “should not have taken place”, were “unlawful” and that police “misled” the magistrate who approved them.
But the IOPC investigation found no evidence the five officers investigated had deliberately misled the judges and said they would have no case to answer for misconduct.
Sir Richard said the IOPC report into the inquiry was “flawed” and “fell well short of an effective investigation”.
Sir Richard’s review was partly published by Scotland Yard last week.
Mr Proctor said the IOPC was “not an independent body that the public can trust” and called on the home secretary to abolish and replace it with “experts who are genuinely qualified to assess and to criticise police failings”.
The former Conservative MP said the IOPC report attempted to excuse police mistakes “by saying they acted in good faith”, with the intention of maintaining public confidence in the aftermath of the Jimmy Savile abuse scandal.
“But this is not acting in good faith – it is acting to interview under caution and search the homes and office of people without evidence in order to help public relations,” he said.
Mr Proctor’s lawyer Geoffrey Robertson QC said this was an “improper motive” and it was “outrageous that the IOPC should think it is a valid excuse for accusing innocent men of heinous crimes or misleading a judge to obtain a search warrant for their homes”.
Writing in the Daily Mail newspaper, Sir Richard said the police watchdog embarked upon a “lamentably slow and inadequate process” in reviewing the work of five Metropolitan Police detectives involved in obtaining search warrants.
He wrote: “Who guards the guards themselves? Who watches the watchers? A malfunctioning police force has not received the necessary oversight.”
“The home secretary will wish to address these shocking failures,” he added.
Sir Richard said the officers’ belief that Beech had “remained consistent” in his accounts of sexual abuse was incorrect and that police “failed to disclose seven factors that undermined Beech’s credibility”.
He added that the IOPC only contacted him after after 20 months, and then told him that two of the five officers under investigation had already been cleared.
The IOPC continued to investigate three officers, but they retired before it published its findings.
Sir Richard said he was “alarmed by the [IOPC’s] lack of knowledge of relevant criminal procedure”.
He added: “I readily conclude that one or more of the five officers may not have committed misconduct in the application for warrants.
“However I find it difficult to conceive that no misconduct or criminality was involved by at least one officer.”
The IOPC said that its review of the officers’ work “was not a cursory exercise” and “independent and impartial”.
A spokesperson said: “This was a thorough and detailed investigation, reviewing over 1,800 documents, 300 statements gathering 14 independent witness accounts and gaining accounts to three officers who were under investigation.
“As Sir Richard writes ‘no subject should be tried without proper investigation’. And, as he acknowledges in his own review, the IOPC is the right and correct authority to do this. Our investigation was both independent and impartial.
“To suggest there is no accountability is also wrong. Our report contains 16 learning recommendations that advocate systemic change so this never happens again.”
Last week, the Met’s deputy commissioner Sir Stephen House said that he was “deeply, deeply sorry” for the pain caused by the Met’s “serious mistakes” during Operation Midland but that the force did not accept everything in Sir Richard’s report.
Home Secretary Priti Patel has ordered an inspection by the chief inspector of constabulary, following Sir Richard’s review.