A senior High Court judge has refused a government request to reconsider a tribunal's decision to prevent a murderer being deported to Italy.
Learco Chindamo could be freed next year
Learco Chindamo, the murderer of London head teacher Philip Lawrence, could be released from prison next year.
An immigration tribunal had ruled that Chindamo, jailed in 1996, could not be deported when he is freed.
The government wanted to challenge the ruling but the judge refused to allow the case to be reconsidered.
Italian-born Chindamo, now 27, stabbed Mr Lawrence at the gates of his west London school when he was 15.
Mr Lawrence was trying to protect another pupil at the time of the incident.
Philip Lawrence was trying to protect another pupil when he was stabbed
In Wednesday's ruling in the High Court, Mr Justice Collins, upheld the Asylum and Immigration Tribunal's decision that Chindamo cannot be deported on release, when he becomes eligible for parole next year.
He said: "There is no error of law in the careful determination of the tribunal."
The judge emphasised his decision was mainly based on EU regulations and the fact that it would be "disproportionate" to remove Chindamo, as an EU citizen, under those regulations.
Although he was born in Italy, Chindamo has lived in the UK since the age of six.
The Asylum and Immigration Tribunal ruled in August that while Chindamo had committed an extremely serious crime, he no longer posed a serious threat to society.
It said it had seen several reports of Chindamo's conduct in detention, saying he had made "a real effort to put his past behaviour behind him and had impressed those responsible for his care with his genuine remorse".
It could not be said that he presents no risk of reoffending "but the risk is assessed as low".
The Home Office has said it has no more legal avenues to follow in the Learco Chindamo case but is "extremely disappointed" with the High Court's judgement.
A spokesman said: "We appealed to the High Court because we believe that all foreign nationals who commit a serious crime should be deported from the UK.
"This judgement will not stop us pursuing deportation against all foreign nationals who commit a serious crime."
Wednesday's ruling will come as a blow to immigration minister Liam Byrne, who says the government wants foreign nationals who commit serious crimes to be "automatically deported".
It also follows news on Wednesday that a serious sex offender has been given the right to stay in Britain because deporting him to his native Sierre Leone would breach his human right to a family life.