By Alexis Akwagyiram
Stephen Lawrence was murdered by a gang of white youths
The murder of Stephen Lawrence in 1993 shocked the UK and led to changes in policing and race relations.
As a memorial service was held to mark the 15th anniversary of his death, BBC News considers the legacy of his murder.
On the night of 22 April 1993, Stephen Lawrence's life ebbed away.
The 18-year-old A-level student collapsed and died in a pool of blood after being stabbed at a bus stop near his home in Eltham, south-east London.
The inquest into his death ruled the teenager was "unlawfully killed in a completely unprovoked racist attack by five white youths".
Some 15 years later, his mother - Doreen Lawrence - said her pain remained "undiminished".
"The campaign for justice continues," she said, referring to the fact that his killers had never been convicted.
While his killers have not been punished, the violent death of the innocent teenager had major ramifications across the UK which can still be felt.
Such was the cultural impact of his death that hundreds of people, including the prime minister, attended a memorial to mark the anniversary.
We do not believe that the Met is institutionally racist - there have been huge changes for the better within the organisation over the last 15 years
The fallout from his murder - and the way it was investigated - altered the way the police and judiciary operate and changed the nature of race relations.
As Mrs Lawrence put it: "Much has changed in the last 15 years and it is some comfort that out of such tragedy has come great improvements in the way the police and other organisations deal with race and diversity issues.
"Britain as a whole has changed too, mainly for the better."
The inquiry into the failure of the Metropolitan Police investigation to find and convict Stephen's killers, headed by Sir William Macpherson, famously concluded that the force was "institutionally racist".
Now, 15 years on, the police force said "huge changes" had been made to ensure this was no longer the case.
"There have been huge changes for the better within the organisation over the last 15 years and while there is always more work to be done, we are proud of what we have achieved so far," said a Met Police spokesman.
"The Met is committed to working with communities to provide the policing service they expect," he added.
By way of example, he pointed to Independent Advisory Groups (IAG), which aim to involve community members with policing decisions and policy-making, and Community Safety Units, which aid the investigation of hate crimes across London.
The Met Police added that recruitment of employees from ethnic minorities was "occurring at an unprecedented rate" - now accounting for almost a quarter of all new police recruits.
The issue of race relations in policing became a national issue of interest to forces across the UK, although the Macpherson Report's criticisms were levelled specifically at the Met.
But how much has really changed?
Since the report, which was published in 1999, police officers have been required to fill out forms each time they stop someone for questioning.
The change, recommended in the report, was introduced because of disparities in the use of stop-and-search, such as unrecorded and temporary stops of vehicles driven by black or Asian people.
It was hoped the forms would monitor whether ethnic minorities were being unfairly targeted as well as the actions of individual police officers.
However, government figures suggest black people are still six times more likely to be stopped than white people, and Asian people are twice as likely.
Doreen Lawrence says her pain remains "undiminished"
Both Labour and the Conservatives recently called for greater use of stop-and-search powers to reduce gun and knife crime.
It came after Conservative leader David Cameron condemned the use of "stop and account" forms as a "colossal waste of police time", arguing that black and Asian communities suffered most from knife and gun crime.
The National Black Police Association (NBPA) says institutional racism still exists in some degree within all police forces.
"The failure of a significant number of forces to achieve the 10-year targets and the continued high level of disproportionality in stop-and-search are indicators of institutional racism," a NBPA spokesman said.
However, the NBPA acknowledges "the extensive work which has been done by police services across the UK to change the dynamic of policing since 1999".
And it points to wider consultation of minorities and the use of role models as examples of efforts being made to address the problem.
Another consequence of Stephen's killing has been the abolition of the 800-year-old double jeopardy rule as part of the Criminal Justice Act 2003, which had prevented a person being tried twice for the same crime.
The change, recommended by the Macpherson Report changed the way criminal cases are prosecuted.
Gary Dobson, Neil Acourt, Luke Knight, Jamie Acourt, and David Norris were arrested over Stephen's murder but the Crown Prosecution Service failed to prosecute anyone due to insufficient evidence in 1994 and again in 2004.
Mr Dobson, Mr Knight and Mr Acourt were acquitted of murder after a private prosecution brought by the Lawrence family collapsed at the Old Bailey in 1996.
In November, the Metropolitan Police said they were reinvestigating new forensic evidence and, since the abolition of the double jeopardy, the men could face another trial.
New DNA samples are being taken from people who may have been in contact with Stephen around the time of this death - such as his family, police officers, ambulance and medical staff - with the aim of eliminating their DNA from enquiries.
Despite the changes that have emerged in the wake of Stephen's death, the racism which claimed his life still exists.
A granite memorial plaque, near the bus stop where the teenager has been vandalised on at least three occasions - in 1998, 1999 and 2002.
And only two months ago, the Stephen Lawrence Centre in Deptford, south-east London, was attacked by vandals.
Six windows were smashed, causing damage valued at £120,000, in what police believe was a racially-motivated attack.
The educational facility had only been open for a week.