Two officers from a heavily-criticised sex crime unit could face criminal charges linked to claims that records were faked.
The Independent Police Complaints Commission (IPCC) has passed files on a detective constable and a police constable to prosecutors.
The Metropolitan Police detective, who was referred to the IPCC in 2012, is facing claims that he faked entries on the crime reporting system about submission of exhibits, advice from the Crown Prosecution Service and authorities from senior officers.
The constable is accused of a potential conspiracy with the detective.
The claims against the detective emerged in May 2012 after a review of 21 of his live cases. The IPCC then also told the Met to look at 38 cases he had closed.
He was arrested the following month on suspicion of perverting the course of justice, and remains on bail.
Scotland Yard's Sapphire unit, since overhauled and re-named, came under fire for a series of failings dealing with rape and sexual assault cases.
A review by the IPCC, published last year, found that officers based in Southwark, south London, had pressured victims into withdrawing their claims in a bid to boost detection rates.
The investigation, which focused on the Southwark unit between July 2008 and September 2009, revealed that a woman who accused Jean Say of rape was pushed to drop the allegation.
Say went on to murder his son and daughter when they went to stay with him for a weekend.
The force has previously been criticised for failures over serial sex offenders sports coach Kirk Reid and taxi driver John Worboys.
A report found the officers did not allocate sufficient resources to catch Reid or get a grip on the sprawling case during a bungled six-year inquiry.
It was recommended that three officers should face gross misconduct proceedings over blunders in the case, but these did not take place. It emerged last year that two of the officers had since been promoted.
Claims were also made that police missed a series of chances to catch Worboys, who sexually assaulted a string of women passengers between October 2006 and February 2008.
One victim alleged that officers laughed at her when she reported being attacked by Worboys as he drove her from central London to Eltham in July 2007.
In another case, Detective Constable Ryan Coleman-Farrow, who was based in Southwark, was jailed for 16 months in October 2012 for failing to investigate rape and sexual assault claims.
He was convicted for a string of failures linked to 13 cases, including falsely claiming that a rape victim had dropped charges and faking witness statements.