The report by a retired judge into the handling of historic claims of child abuse and murder by prominent figures of the establishment has been delivered to Scotland Yard.
The inquiry into Operation Midland by Sir Richard Henriques is expected to criticise the force. Police chiefs will study the report before deciding what will be published and what will remain secret.
The review examined how police forces can maintain the confidence of victims, while avoiding the appearance of believing any story they are told.
The Metropolitan police describes the version they have received as a “draft” and will now also decide which of Henriques’s findings they agree with.
The force says there is “no timetable” for the publication of the limited excerpts they will publish, but has said it will not publish the full report because it contains confidential and sensitive information.
It is believed this refers to information about and from exonerated suspects and their accusers.
A Met police spokesman said: “We have received the draft report. Sir Richard Henriques will finalise the report in the coming weeks.”
The £2m Operation Midland ended in March after it was concluded there was insufficient evidence to arrest anyone or ask prosecutors to consider a charge.
The Met and its soon-to-be-retired chief, Sir Bernard Hogan-Howe, are expected to face strong criticism for relying on the testimony of a single alleged abuse victim named as “Nick”, who claimed politicians and military figures abused children in London and the home counties between 1975 and 1984.
Nick’s claims led to allegations against public figures including Edwin Bramall and Leon Brittan and the former Conservative MP Harvey Proctor. All denied the allegations against them.
Launching the review in February, the Met said: “The key findings of the review and the recommendations will be published later this year, but the full review will contain confidential and sensitive information and will be a private report for the commissioner.”
The Met believes scores more victims of sexual abuse will come forward, leading to more cases like those of Brittan and Bramall in which prominent figures face allegations. He adds that despite improvements to police practice “many more women” who suffer rapes “still don’t come forward”.
Hogan-Howe has supported a new law banning news organisations from naming suspects in sexual abuse cases until they are charged.
Hogan-Howe will retire as commissioner in February 2017.