The two boys convicted of murdering the toddler James Bulger were yesterday granted permission to take their case to the European Court of Human Rights.
Jon Venables and Robert Thompson, both now 15, have alleged that their trial in an adult court was "inhuman and degrading" treatment and the Home Secretary, then Mr Michael Howard, should not have been able to set their "tariff" on how long they should serve in prison.
The European Commission of Human Rights, in Strasbourg, yesterday ruled that the boys' complaints were admissible but it could be years before the court gives a ruling on the case.
Even then, the boys would not be retried or their sentence reduced, but a ruling in their favour would force the British government to change the way it tried children accused of serious offences. And it would also force the government to review the system which allows home secretaries to decide how long children detained "at Her Majesty's pleasure" should serve.
The two boys were just 10 when they were convicted in 1993 at Preston Crown Court, Lancashire, of kidnapping two-year-old James Bulger from a shopping centre in Bootle, Merseyside, and murdering him on a railway line.
The judge sentenced them to be detained at Her Majesty's pleasure, recommending a minimum of eight years. This was later increased to 10 years by the Lord Chief Justice and after a massive campaign led by James's mother, Denise, the home secretary, Mr Howard, further increased the tariff to 15 years. This was quashed last year by the House of Lords, and the Home Secretary, Mr Jack Straw, now has to decide on a new tariff for the two.
At yesterday's in camera hearing lawyers for the boys argued that they were denied a fair trial because the proceedings took place in an adult court which the boys could not understand or participate in.
Karen Bulger, James's aunt, told PA News: "I think it's the wrong decision.
"They got a fair trial. They were treated as kids, they were interviewed as kids by the police.
"They should stop doing this and accept their punishment."
Rex Makin, solicitor for James's father Ralph Bulger, said: "So far as the boys are concerned, the position is that every time there is one of these incidents the knife is turned further into the wound of the grief of the Bulgers.
"They are not allowed to let matters settle down and let the grieving process begin."
In argument submitted to the Commission, made up of lawyers from the 40 members of the Council of Europe, the boys' lawyers said that the "frightening nature of the ordeal" of their trial had an "destructive and devastating effect" on Thompson and Venables.
They also argued that as the two boys were aged 10 at the time of the murder they should not have been held criminally liable and had been deprived of their liberty by their sentence.
But lawyers for the Government denied there had been any distress caused to the boys and claimed the trial judge had done everything possible to make sure the boys understood the proceedings.
A ruling in favour of the boys could affect scores of children already being held for serious crimes and change the whole system of dealing with minors.
Recently there was massive criticism of the way in which police and Crown Prosecution Service dealt with a group of 10-year-old boys charged with the alleged rape and sexual assault of a 10-year-old girl.
The boys were tried at the Old Bailey but were acquitted amid complaints from their lawyers that they should never have been tried in an adult court.
The European Court of Human Rights has a massive backlog of cases and it could be years before a verdict is reached on this case.
It is the first step for Thompson and Venables in Europe after they exhausted all avenues of appeal in Britain.
Although it is not known what tariff Jack Straw will set for them, he will have to review their case at the halfway stage of their sentence, opening the prospect for their possible release in just a few years.
The murder of James Bulger shocked the nation in February 1993 and led to a massive petition for an increase in the boys' sentence after the initial recommendation of eight years.
John Wadham, director of Liberty, the human rights organisation, said: "The decision of the European Commission of Human Rights is important and we hope it will lead to a fairer system of justice where juveniles are dealt with in appropriate courts.
"And more importantly, only courts and not politicians have a right to decide how long people spend in prison and whether or not they are released."