Controversial historical sex abuse investigations such as the probe set up to examine claims of a VIP paedophile ring in Westminster will be scrutinised by an independent review.
Embattled Scotland Yard boss Sir Bernard Hogan-Howe has called in former High Court judge Sir Richard Henriques to examine a number of investigations involving non-recent abuse claims against public figures.
His force has faced fierce criticism over one investigation, known as Operation Midland, which saw the home of 92-year-old Lord Bramall raided before the case was later dropped.
The move comes as a decision is imminent as to if and for how long Sir Bernard's contract as Metropolitan Police Commissioner will be renewed.
He said: "We are not afraid to learn how we can do these things better, and that's why I've announced today's review into how we have conducted investigations into non-recent sexual allegations involving public figures.
"I am pleased that Sir Richard brings an independent legal mind to advise us whether we can provide a better balance between our duty to investigate and the interests of suspects, complainants and victims."
Key findings of the review will be published later in the year, although the full report will remain confidential.
An Independent Inquiry into Child Sex Abuse is already being led by Justice Lowell Goddard, and is expected to cost £18 million in its first year, but Sir Bernard said this probe will look at police procedure, not evidence.
He said: "The review will focus on police procedures and will not reach judgments on the evidence. That is for the Public Inquiry to do, should they wish to examine any of the investigations covered by Sir Richard. A full copy of the review will be given to the Public Inquiry."
Operation Midland was launched in November 2014 following allegations that boys were sexually abused by a paedophile ring centred around Westminster more than 30 years ago.
There were claims that sex parties were held at the exclusive Dolphin Square apartment block near the Houses of Parliament.
The inquiry centred on allegations by a man known as "Nick", and was also looking into the alleged murder of three young boys.
At the time a detective described Nick's account as "credible and true".
Former Tory MP Harvey Proctor, who furiously denied any involvement and claimed he was the victim of a homosexual witch hunt, has been interviewed under caution twice but has not been charged.
Former prime minister Edward Heath and ex-home secretary Lord Brittan, who are both now dead, have also been named in connection with the probe.
Operation Midland, which had cost £1.8 million as of November last year, has come under intense scrutiny in recent weeks after the Met announced that D-Day veteran Lord Bramall would face no further action over historical child abuse allegations.
The development sparked calls for police to offer an apology to the former armed forces chief and prompted questions over the veracity of Nick's claims.
Scotland Yard has also come under fire over its handling of a separate allegation that Lord Brittan raped a 19-year-old woman known as "Jane" in 1967. He died in January last year without being told he would not face action over the claim, made to police in November 2012.
Police originally determined that the complaint against Lord Brittan should not be pursued more than a year before he died. But the investigation was reopened and he was interviewed under caution in May 2014 while suffering from terminal cancer.
The Met submitted a file to the CPS in November 2014 but was told it would not be considered. The force then appealed that decision and claimed that, even though it had concluded there was not a strong case against Lord Brittan, he could not be informed that no action would be taken at that point.
In October police apologised to Lord Brittan's widow, saying she should have been informed there would not have been a prosecution had her husband been alive in April this year.
The NSPCC warned that victims should not be put off coming forward.
A spokesman for the charity said: "We welcome a thorough and independent review of this case and hope that lessons can be learned; it is clear that damage has been done. But whilst it's important to assess its handling, it is crucial that this review does not inadvertently discourage victims of abuse from coming forward.
"For someone to talk about the cruelty they endured takes unimaginable bravery, and they must feel confident that they will be listened to. We must not return to the dark ages where some powerful people believed themselves to be untouchable, and victims thought they would be disbelieved and dismissed."
There have been claims in recent weeks that Operation Midland is on the brink of collapse.
However, following the announcement of the review a Met spokeswoman said the inquiry is "still ongoing".
Lord Bramall's solicitor Drew Pettifer said: "Lord Bramall welcomes any review that can assist the police in making improvements in the way they investigate such allegations, thus making the process fairer and less painful for all those concerned."