The murder of Philip Lawrence, the headmaster who went to the aid of a pupil being attacked by a teenage gang, aroused a national sense of revulsion that, 12 years on, has not subsided. He died of stab wounds inflicted by Learco Chindamo, a violent and illiterate boy of 15. He was sentenced to life imprisonment with a tariff that, taking his age into account, was set at 12 years.

The Government, anticipating his release on parole next year, intended to deport Chindamo, now aged 26, to his native Italy, where he was born to an Italian father and a Filipina mother.

It has been barred from so doing by the Asylum and Immigration Tribunal, in a ruling that has far-reaching implications for public policy and that has caused anguish to Mr Lawrence’s widow and children and bewildered the public. It is, therefore, wholly contrary to the good administration of justice in this country, based as it must ultimately be on public trust, that secrecy has enveloped every aspect of this important case.

The tribunal, disdainfully referring to “hysterical misinformed articles in the gutter press”, decided to ensure that the press could not be informed, by excluding the media from the hearing in order “to protect the private life of the appellant”. The Home Office and the Judicial Communications Office declined to make the tribunal’s ruling public – even after Chindamo’s solicitor had told the BBC Today programme that the tribunal had ruled that deportation would violate his client’s rights to a full and fulfilling family life, guaranteed by the Article 8 provisions of the Human Rights Act. The natural public reaction was to ask about the family life of the Lawrences.

The Home Office had no business withholding the ruling and its accompanying arguments. As a party to the case, it was entitled to release the document, as the public interest clearly required. Asylum and Immigration Tribunal normal practice is to keep rulings confidential, for the good reason that personal suffering and state persecution often figure in the hearings. This emphatically was not that kind of case. In the event, the document had been loaded on the tribunal’s own website, where it was discovered by The Times. We have published it on our website, placing it in the public domain where it belongs.

The ruling on the appellant’s right to a family life should, as laid out, calm indignation; it is nuanced, dry-eyed and broadly persuasive that Chindamo’s links with Italy, which he left at the age of 5, are too tenuous to justify deportation. Where this landmark ruling packs a dynamite charge is in the section on the appellant’s rights as an EU citizen under the 2004 Citizens Directive, as incorporated last year into British law.

Only last month Gordon Brown insisted that all foreign criminals “will be deported”. Yet under EU law, the Government has known for three years that it has no such powers. Each case must be considered on merit and, no matter how repugnant the crime, the only permissible grounds for deportation are “a genuine, present and sufficiently serious threat” to society’s “fundamental interests” or “imperative grounds of public security”. No one fitting that description would be recommended for release by the Parole Board. As the Home Office solicitor complained at the hearing, so long as the criminal has lived in this country for five years or more – whether or not at Her Majesty’s Pleasure – Britain “could never deport a lifer who had been released from prison and was an EU citizen”. Is that why the Chindamo case was kept secret?