Stephen Lawrence murder: Police corruption inquiry
Claims a confidential report from the Metropolitan Police's anti-corruption command was not given to the inquiry into the handling of Stephen Lawrence's murder are to be investigated.
The Independent Police Complaints Commission (IPCC) will examine if the document was disclosed to the 1998 Macpherson inquiry.
A previous IPCC inquiry concluded there was no evidence of corruption.
Gary Dobson and David Norris were convicted of the murder in January.
Stephen Lawrence was 18 when he was stabbed to death near a bus stop in Eltham, south-east London, in April 1993.
The force refused to disclose again if two months of searches by its own detectives had uncovered any evidence that reports had not been passed on to Macpherson.
In a statement the Met said: "The Directorate of Professional Standards has reviewed a considerable number of files and reports dating back to the 1980s as well as conducting interviews with a number of key individuals involved in the original investigation into both Stephen Lawrence's murder and police corruption.
"We have retrieved a number of key documents, which greatly assist in understanding what material was available to the Macpherson inquiry and are now in the process of sharing our findings with the IPCC so that they can review it in the light of their previous involvement in the case."
The announcement comes after Stephen's mother, Doreen Lawrence, called for the reopening of the major public inquiry into the circumstances of his death.
She has written to the Home Secretary Theresa May about her concerns that the initial 1993 investigation involved corrupt police.
Ms May has since offered to meet Mrs Lawrence, who said the claims gave further impetus to her calls for a public inquiry.
In October 2007, the IPCC carried out a year-long inquiry into claims the first police inquiry into the murder was hindered by a corrupt officer.
The claims were made in a BBC programme in July 2006, which reported former police detective Neil Putnam saying that Det Sgt John Davidson took a bribe from Clifford Norris, father of David Norris.
The IPCC decided the claims were unfounded.