Allegations that police corruption undermined the inquiry into the murder of black teenager Stephen Lawrence will be investigated by the police watchdog.
Stephen Lawrence was attacked at a bus stop in 1993
The Independent Police Complaints Commission (IPCC) will look into claims made in a BBC documentary that an officer in the case took bribes.
The commission will also try to find out if corruption claims were reported to the police but not investigated.
Stephen was stabbed to death by a gang of white youths in London in 1993.
John Wadham, of the IPCC, said he would discuss the terms of the inquiry with Stephen's parents, Neville and Doreen Lawrence.
But Mr Wadham said the starting point of the investigation would be claims made in the BBC documentary, The Boys Who Killed Stephen Lawrence.
"The first is that an officer, or officers, may have received bribes and secondly, that this claim had been reported to the MPS [Metropolitan Police Service] but not investigated."
The Met Police promised to give their full co-operation, Mr Wadham added.
Neville and Doreen Lawrence made separate complaints to the IPCC, kick-starting the commission's inquiry, after hearing of the claims in the BBC documentary.
Neville Lawrence has said he "always thought that there was something to do with corruption".
The police insisted that the murder case was still open and encouraged anyone with information to come forward.
The Archbishop of York has offered to help out in the Lawrence case if people were scared to go directly to the police.
Dr John Sentamu told the BBC: "If you really have evidence ... please, please tell it to the police.
"Or if you are scared of telling the police, get in touch with the Archbishop of York, and I'll handle your evidence for you."
The IPCC investigation announcement comes the day after Paul Stephenson, deputy commissioner of the Met Police, said his determination to pursue corrupt officers was "undimmed".
Mr Stephenson said cases of alleged corruption were the "most difficult" and "most deeply unpleasant" investigations, but promised to work with the IPCC.
The original Met Police investigation into Stephen's death led to the Macpherson Inquiry - which accused the force of "institutional racism".
Neil Acourt and four other suspects appeared at the Macpherson Inquiry
Five men - Neil Acourt, his brother Jamie, David Norris, Gary Dobson and Luke Knight - were arrested after the initial investigation but were never convicted.
A second police investigation revealed them to be a gang of racists who had an obsession with knives.
The BBC's documentary accused Det Sgt John Davidson of taking bribes from Clifford Norris, father of suspect David Norris. The retired detective denies any wrongdoing.
Eighteen-year-old Stephen was stabbed to death at a bus stop in Eltham, south-east London.