Britain's former top police officer is to be investigated over his evidence to the official inquiry into Scotland Yard's handling of the murder of black teenager Stephen Lawrence.
Former Metropolitan Police commissioner John Stevens faces an investigation over his disclosure to the Macpherson Inquiry in 1998, which found evidence of "institutional racism" within the force, the Independent Police Complaints Commission (IPCC) said.
Stephen, an 18-year-old would-be architect, was stabbed to death by a group of up to six white youths in an unprovoked racist attack as he waited at a bus stop in Eltham, south-east London, with a friend on April 22 1993.
A second review last year by Mark Ellison QC found that corruption allegations about a Metropolitan Police detective who worked on the original investigation into his killing should have been revealed to the public inquiry led by Sir William Macpherson.
Imran Khan, the solicitor of Stephen's mother, Baroness Lawrence, told Sky News she welcomed the IPCC decision, adding: "One of the issues that we wanted to raise at that (Macpherson) inquiry was the issue of (police) corruption. We weren't able to get to the bottom of it because William Macpherson said there wasn't the foundation for us to investigate that.
"Clearly there are concerns about whether there was full and frank disclosure by the Metropolitan Police of the information that would have given rise to us investigating it further than we did at the time."
News of the investigation came as crossbench peer John, now Lord Stevens, backed a pledge by Labour to protect the jobs of 10,000 bobbies on the beat, saying it was the "right plan".
Under Labour's proposals, p olice and crime commissioners (PCCs) would be axed to help fund the £800 million plan to guarantee neighbourhood policing across England and Wales.
A victims' law setting out rights for people affected by crime would also be introduced.
Lord Stevens, who headed an independent commission on policing by the Labour party, said: "It is not credible to say you can take away resources on the scale the Government are talking about without wiping out neighbourhood policing.
"And it doesn't show the right priorities to be spending significant sums on police and crime commissioners, nor to be ideologically opposed to the shared services and joint procurement that simply must be driven through."
Bringing two of Stephen's killers - Gary Dobson and David Norris - to justice took more than 18 years.
The pair were jailed for life in January 2012 for their role in the group attack.
Mr Ellison's major review of the case found evidence to suspect one of the detectives on the original murder investigation acted corruptly.
It found there was a high level of suspicion that former Detective Sergeant John Davidson was corrupt both before and after he worked on the police investigation.
The Ellison report said that, in late July 1998, Scotland Yard's Anti-Corruption Command held a debriefing with former Detective Constable Neil Putnam, in which he made claims against Mr Davidson.
The barrister said that both the intelligence picture suggesting Mr Davidson was a corrupt officer and the content of Mr Putnam's debriefing should have been revealed to the public inquiry led by Sir William Macpherson.
"It is a source of some concern to us that nobody in the MPS who was aware of the detail of what Neil Putnam was saying about Mr Davidson appears to have thought to ask him about Mr Davidson's motives in the Lawrence case," the report says.
The Ellison report led Home Secretary Theresa May to announce a judge-led public inquiry into the work of undercover officers.
Stephen's father, Neville Lawrence, told Channel 4 News: "I'm glad that they're actually doing what they were supposed to do because this is not the first time that we've asked them to look into it and they've come back with a negative result.
"I'm hoping that this time they're going to come back this time with a result that can help us to get further into the truth of what was happening during the investigation into Stephen's death."
Scotland Yard said it had referred the matter to the IPCC last November after a complaint made by Neville Lawrence following the damning review of the Lawrence case by Mr Ellison.
The Met spokeswoman said: "The complaint has been made in relation to Lord Stevens's role as the then deputy commissioner and disclosure to the Macpherson Inquiry.
"This issue was raised in the Stephen Lawrence Independent Review by Mark Ellison QC, published on March 6 (last year), where he concluded there were defects in the level of information that the MPS revealed to the inquiry."
An IPCC spokeswoman said: "We can confirm we are independently investigating Lord Stevens following a referral from the Metropolitan Police."
Lord Stevens of Kirkwhelpington was Britain's top police officer until retiring from the post in 2005 after five years. He then headed inquiries into the circumstances surrounding the death of Diana, Princess of Wales, and alleged football bungs.
The former Met detective was appointed assistant chief constable of Hampshire Constabulary in 1986, before becoming deputy chief constable of Cambridgeshire Police two years later. He became chief constable of Northumbria before being made deputy commissioner of the Met in 1998, with responsibility for leading the fight against corruption in the force.