THE mother of murdered teenager Stephen Lawrence has launched a campaign to mark the 20th anniversary of his death - exactly a year after his killers were convicted.

The 18-year-old A-Level student was fatally stabbed in an unprovoked attack as he waited for a bus in Eltham in April 1993.

Doreen Lawrence said more would be done this year to ensure no other family has to go through what she suffered, including an outreach programme to new police chiefs.

Elsewhere, a concert planned for April, a criminal justice lecture, an annual memorial lecture and a gala ball will help raise awareness and funds.

Mrs Lawrence, who founded the Stephen Lawrence Charitable Trust, said: "It is hard to believe that 2013 will mark 20 years since Stephen died.

"This time last year we faced the conviction of two of Stephen's killers and the relief I felt then has stayed with me through the extraordinary year that was 2012.

"Despite this, our focus has to be on the next 20 years. There is more to be done to get justice for Stephen and to ensure that no other family has to go through what we endured."

She said the trust would campaign to new police and crime commissioners for fairer community policing.

A memorial service will be held at St Martin in the Fields in Trafalgar Square on April 22 - the date Stephen died 20 years ago - as part of the so-called SL20 Campaign.

Gary Dobson and David Norris were jailed for life last January for Stephen's murder, while Ms Lawrence continues to press for the tracing and arrest of others involved in the murder.

During the trial, the court heard a gang of five or six white youths set upon the teenager in Eltham.

The Metropolitan Police faced fierce criticism over the original investigation into Mr Lawrence's death.

A public inquiry branded the force institutionally racist and claims were made by Mr and Mrs Lawrence's lawyers that some officers were influenced by Norris's former drugs baron father.