What they cannot for the life of them understand is how on earth Zahid Mubarek was ever allocated to share a cell with this monster

Patrick O'Connor QC for family

On Tuesday the High Court ruled that the home secretary must hold "an independent investigation", under Article 2 of the European Convention on Human Rights.

Unless there is an appeal, Mr Blunkett will have to consider what form of "independent investigation" should be ordered.

The full reasons for Mr Justice Hooper's decision will be given in October.

Ku Klux Klan

Robert Stewart, 20, was sentenced to life in November for battering Mubarek around the head with a table leg.

Mubarek, of Walthamstow, north east London, was attacked hours before he was due to be released after a 90-day sentence for dishonesty. He died a week later.

Steward: "Obvious" racist

The High Court had been told by Patrick O'Connor QC, for the family, that it was obvious that Stewart was a dangerous racist - for example there was a Ku Klux Klan sign openly displayed on the notice board of the pair's cell.

"What they cannot for the life of them understand is how on earth Zahid Mubarek was ever allocated to share a cell with this monster.

"It defies rational analysis, and the Butt Report (the result of an internal Prison Service inquiry) for all its substance has utterly failed to provide any explanation for it."

'Institutionalised racism'

Prison Service director general Martin Narey has previously apologised to Mr Mubarek's family.

Solicitor Imran Khan has accused both Feltham and the Prison Service of negligence and institutionalised racism.

After the ruling Mr Khan said: "This is a fantastic result which is ground-breaking in many ways.

This was a young man convicted of a first offence who should not have been in prison

Frances Crook Howard League of Penal Reform

"It is also a huge embarrassment for the home secretary."

Mr Mubarek's uncle, Mr Amin, who launched Tuesday's legal action, said: "We are now one step nearer to the truth and Zahid did not die in vain.

"At least in this way we can ensure something like this does not happen again."

Prison reform campaigners also welcomed the judge's decision as a "a fantastic victory for the public good".

Frances Crook, director of the Howard League for Penal Reform, said: "I hope the implications of this will go far and wide, because when there are unexplained deaths in custody the public has a right to know what's going on.

"Then changes can be made and people protected. This is a fantastic victory for the public good."

First offence

Ms Crook said that whatever form of independent inquiry goes ahead into Mr Mubarek's death, it should not be limited to failures inside Feltham Young Offenders' Institution in west London.

"This was a young man convicted of a first offence who should not have been in prison.

"The magistrates who sent him there ... should be investigated.

"If he had not been sent to Feltham in the first place he would still be alive."

The Metropolitan Police is understood to have passed a file to the Crown Prosecution Service to decide if any charges should be brought against staff at the institution for failing to avert the murder.