Doreen Lawrence reacts to news that David Norris and Gary Dobson will stand trial for the murder of her son Stephen Lawrence Press Association

Two men are to stand trial accused of being part of a racist white gang that "targeted and killed" the black teenager Stephen Lawrence because of the colour of his skin, the appeal court has said.

The killing in 1993 in Eltham, south-east London, is one of the most high-profile unsolved murders in Britain.

The men charged are David Norris, who has never before been charged over the stabbing, and Gary Dobson, who stood trial previously and was found not guilty.

Dobson was acquitted of killing Lawrence, 18, after a private murder prosecution brought in 1996 by the parents of the talented youngster who dreamed of being an architect.

A new law established in 2003 abolished the longstanding ban on people being retried for the same crime after being found not guilty, if "compelling" new evidence came to light.

The appeal court agreed on Wednesday that new evidence was compelling enough to allow Dobson's acquittal to be quashed.

In effect, the appeal court, in a ruling by the lord chief justice of England and Wales, wiped the legal slate clean. This means Dobson and Norris will stand trial for the murder of Lawrence, in November at the Old Bailey in central London.

David Norris and Gary Dobson. Photograph: CPS

The Crown Prosecution Service and police charged Dobson and Norris in September 2010, but some of the toughest reporting restrictions on the media meant the dramatic development in the long-running case could not be reported until now.

In March, a hearing was held at the appeal court to decide if the acquittal of Dobson could be set aside, watched by Lawrence's parents, Doreen and Neville. The media was also banned from reporting that hearing.

The judgment says the murder of Stephen Lawrence was a "calamitous crime" and declares he was "a young black man of great promise, targeted and killed by a group of white youths just because of the colour of his skin".

The new evidence that convinced the appeal court to quash Dobson's acquittal is based on forensics.

The media is restricted in its reporting to Wednesday's judgment from the court of appeal.

According to a summary of its judgment: "The present application depends on the reliability of new scientific evidence which by reference to the grey bomber jacket (LH/5) and the multi-coloured cardigan (ASR/2) closely links Dobson with the fatal attack on Stephen Lawrence.

"It does not and could not demonstrate that Dobson wielded the knife which caused the fatal wound, but given the circumstances of the attack on Stephen Lawrence – that is, a group of youths in a violent enterprise converging on a young man, and attacking him as a group – it would be open to a jury to conclude that any one of those who participated in the attack was party to the killing and guilty of murder, or alternatively manslaughter (a verdict which would, if there had been sufficient evidence, also have been available at the first trial).

"If reliable, the new scientific evidence would place Dobson in very close proximity indeed to Stephen Lawrence at the moment of and in the immediate aftermath of the attack; proximity, moreover, for which no innocent explanation can be discerned."

Counsel for Dobson, Timothy Roberts QC, argued the new forensics were unreliable because they "are likely to be the product of contamination over the years, that is, by contact with Stephen Lawrence's blood and his clothing". This was "the result of outdated or incompetent storage or packaging or transporting arrangements".

Furthermore, Roberts said Dobson's acquittal should stand because "the huge wave of constant publicity over the years, directly identifying some of those suspected of the murder with involvement in the crime" meant there could not be a fair trial.

In the judgment by the lord chief justice, the appeal court decided there was enough new evidence for Dobson to stand trial for Lawrence's murder for a second time: "There is sufficient reliable and substantial new evidence to justify the quashing of the acquittal and to order a new trial.

"This decision means – and we emphasise that it means no more than that – the question whether Dobson had any criminal involvement in Stephen Lawrence's death must be considered afresh by a new jury, which will examine the evidence and decide whether the allegation against him is proved. The presumption of innocence continues to apply."

The judgment states that its ruling does not mean that Dobson is guilty and stresses that the court of appeal "is certainly not required to usurp the function of the jury, or … indicate to the jury what the verdict should be".

Lawrence was murdered just after 10.35 pm on 22 April 1993. He was waiting at a bus stop in south-east London with a friend, Duwayne Brooks.

According to the judgment: "As they waited peacefully for the bus, a group of white youths crossed the road towards them. One of the youths used abusive racist language. This was followed by a sudden and immediate attack, as the group converged on or charged at them.

"Duwayne Brooks managed to make his escape, but Stephen Lawrence was felled.

"He was stabbed twice to the upper torso … Major blood vessels were severed. The injuries were fatal.

"Mortally wounded, Stephen Lawrence managed to get to his feet. He ran after Duwayne Brooks, but after a little while, he collapsed on the pavement. He died shortly afterwards in hospital."