Scotland Yard chiefs are said to be shocked by the scathing criticism doled out by retired judge Sir Richard Henriques about their handling of the £2million Operation Midland.

Sir Richard is believed to have concluded that it should have been shut down before March because there wasn’t enough evidence to arrest suspects let alone prosecute them.

His report is said to question why detectives gave so much credibility to star witness ‘Nick’ even though there were inconsistencies in his evidence.

The flawed investigation also appeared unlikely to meet the evidence threshold required to get suspects into the dock.

The Guardian has said there is still no timetable for the release of Sir Richard’s report, and say Met officers criticised in the report are demanding a ‘right of reply’.

Operation Midland has been widely criticised, in part because it was based, largely, on the evidence of one man. Victims and their families called it an expensive ‘fishing exercise’.

A senior detective described Nick’s evidence as a ‘credible and true’ at the outset of its investigation into his claims of murder and rape by an Establishment paedophile ring in the 1970s and 1980s.

Nick claimed former MP Harvey Proctor, ex-prime minister Sir Edward Heath, former Tory home secretary Leon Brittan and ex-chief of the defence staff Lord Bramall were involved. But police found no evidence to support his allegations.

After his ordeal Harvey Proctor, who had been accused of assaulting a 14-year-old boy in a town he had never visited almost 25 years ago, said people who make false claims of historic sex abuse should be prosecuted for wasting police time.

Lord Brittan’s widow has repeatedly attacked police and MPs for hounding dead VIPs over baseless child sex allegations.

Discussing Scotland Yard’s disastrous £2million investigation into her late husband and other Establishment figures, Diana Brittan has insisted Sir Bernard Hogan-Howe’s force still had ‘many outstanding questions to answer’.

Lady Brittan, 75, also queried ‘why warrants were issued to search the homes of people who had already died and therefore could never be prosecuted’.

She also queried why the ‘VIP accused’ were subjected to a ‘tougher, longer and more stringent test than other people’.

The London and Yorkshire homes of the late former home secretary were raided after his death from cancer at the age of 75 in January last year.

Police removed clothes, diaries, pictures, computers and phones as his widow grieved.

Ex-Chief of the Defence Staff Lord Bramall, 92, and former Tory MP Harvey Proctor, 69, also had their homes raided under the 16-month probe.

Lord Bramall hit out at police for failing to clear him of baseless paedophile allegations until after his wife had died.

The late former prime minister Edward Heath was also named in connection with the probe.

But it took more than a year for the Met to finally admitted it had found no evidence to support claims made by a man known as ‘Nick’ that Establishment figures were responsible for killing three boys in the 1970s and 1980s.

Sir Bernard Hogan-Howe announced his surprise resignation as Commissioner last month and plans to retire in February. Insiders claim he stepped down after learning his force will be lambasted in the report.