In a submission to the Stephen Lawrence inquiry, Dr Robin Oakley, an independent consultant, says this insidious form of racism may have affected the actions of every officer who investigated Stephen's murder in 1993.
His views will come as a severe blow to the Met, which has admitted that its officers were grossly incompetent but strongly denies allegations of racism. Dr Oakley, a former academic, is eminent in race training. He has worked with the Home Office, the Met and other police forces for many years.
The public inquiry into Stephen Lawrence's death will reconvene next month to examine the lessons to be learnt from the abortive police investigation.
Dr Oakley says definitions of racism need to be re-examined, and that the problem is not - as is believed by many in the police service - confined to "a few rotten apples".
This concept, which gained widespread acceptance after Lord Scarman's report into the Brixton riots in 1981, is at odds with such phenomena as the disproportionate numbers of black men stopped and searched on the streets by police, he says.
"It is quite unrealistic that minority concerns about differentials in stop and search, about the police response to racial attacks, and about police demeanour towards visible minorities generally, could be the result of actions solely of a small number of individuals.
"At the very least, they must be the result of tendencies among a much larger number of officers, if not the outcome of `normal policing'."
Dr Oakley says institutional racism lies at the heart of the problem, and was "potentially - though not necessarily actually manifest in the actions of every officer involved in the events following Stephen Lawrence's murder".
He goes on: "What were the images of Stephen as a young black person in the minds of those who attended the scene, and did they check out any possible tendencies to make assumptions of a racial nature?
"Did they routinely consider and also prioritise the possibility that racism could have been his attackers' motivation? Did they appreciate and respond to the concerns that a black family in particular might have when dealing with police in these kinds of circumstances?"
Dr Oakley says it is not surprising that the Police Complaints Authority, which reviewed the murder investigation last year, found no evidence of overt racism.
"Whether there should be confidence that no racially discriminatory treatment of any kind took place, eg of a more subtle and unintended nature, is an entirely different matter," he says. "In general, there are sound reasons to suppose that biased actions could have occurred."
Dr Oakley says that while subliminal racist attitudes can affect all large organisations, the police service is particularly vulnerable. He says: "Police work, unlike most other professional activities, has the capacity to bring officers into contact with a skewed cross-section of society, with the well-recognised potential for producing negative stereotypes of particular groups.
"Such stereotypes become the common currency of the police occupational culture. If the predominantly white staff of the police organisation have their experience of visible minorities largely restricted to interactions with such groups, then negative racial stereotypes will tend to develop accordingly."
Sir Paul Condon, the Metropolitan Police Commissioner, has said the Met plans to improve training and recruitment procedures to combat racism.
Dr Oakley says an "overall strategic approach" is needed, "implemented at all levels, with the lead visibly from the top".
Last weekend, Dr Oakley said: "It's not about dealing with a small number of bigots; it's about dealing with an organisational culture. Some of these issues are being addressed and some progress has been made, but there is an urgent need for more to be done."Reuse content