A leading policeman has expressed “disappointment” that the killers of David Morley were not convicted of murder.

A teenage girl, who can not be named for legal reasons, and her co-defendants Reece Sargeant, 21, Darren Case, 18 and a youth aged 17, were found guilty of the manslaughter of David Morley on Wednesday.

The gang were also convicted of conspiracy to cause grievous bodily harm. They were cleared of his murder. Barry Lee, 20, and another 17-year-old were cleared of all charges.

Morley, 37, a survivor of the 1999 Soho nail bomb attack, was chatting with a friend on the South Bank when the gang pounced. The girl, who was 14 at the time, told Morley that she was making a documentary about ‘happy slapping’ before the friends kicked him to death.

The court heard that as Morley lay on the ground unconscious, the girl “kicked his head as if it was a football”.

Assistant Commissioner Tarique Ghaffur says he disappointed that the jury did not convict the gang of murder: “the horrific death of David Morley and the brutality of the attack by these young people shocked us all. Their complete disregard for the life of an innocent man and the manner, in which they filmed the attack as a trophy of their actions, is extremely disturbing.

“I am deeply disappointed with the resulting conviction for manslaughter and not murder. Although the suspects were prosecuted for murder the jury decided to return a verdict of guilty to manslaughter as they are permitted to do so by law.

“We worked closely with the CPS on this case and I have asked Commander Dave Johnston, the new head of the homicide command, to work with them to see if there are any lessons that can be learnt as to why the conviction was one of manslaughter and not murder.”

Peter Tatchell of gay rights group OutRage! claims that there appears to be a difference in the way that crimes against gays are treated: “it is questionable whether justice has been done, when there are differential verdicts for such similar hate-motivated killings. It seems that homophobic hate crimes do not attract the same penalties as other hate crimes.”

However, contrary to Mr Tatchell’s allegations, the attack on Mr Morley had been considered as motiveless and random, which indicated to the police that it was not motivated by the fact tat the victim was gay.