A judge ruled that a Pakistani drug dealer could not be deported as it would be "unduly harsh" on his son, whom he teaches "about Islam, about Pakistani culture and his own upbringing".

The Home Office ordered the deportation of Muhammad Asif Karim, 43, after he was convicted seven times for 21 offences, including supplying the Class A drugs heroin and cocaine, serving a four-year jail term. However, the appealed to the Upper Tribunal-an immigration and asylum court-and the judge agreed that under the right to a family life, set out by Article 8 of the European Convention on Human Rights, he should be permitted to stay in the UK to be with his son.

This is despite the court hearing that the child is "largely brought up by his white British mother". The boy gave evidence that his father "is able to talk to him about Islam, about Pakistani culture and his own upbringing". and stay in Britain by appealing to the courts.

The court heard that Karim, who has lived in the UK for 26 years, had avoided criminality for 10 years and enjoyed a "parental relationship" with his son. The tribunal accepted that the talks between the pair were "fundamental" to the boy's identity. In response, the Home Office argued that that was nothing but "conjecture", unsupported by corroboration from a social worker or psychologist.

The tribunal ruled: "Although there is a particularly strong public interest in removing someone who habitually committed crimes over a 14-year period, his last offence was committed over 10 years ago and he has complied with all probation and rehabilitation requirements, as well as the reporting conditions imposed on him by the Home Office," it said.

"He has throughout the relevant period suffered from significant and debilitating mental ill-health, and although this was not a factor that the first-tier tribunal thought significant, it is right to note that there has been an inordinate delay - over 10 years - on the part of the Secretary of State in effecting this deportation.

"There was also evidence that he was himself a survivor of violence, trauma and criminality, all of which had played a role in his troubled youth."

Home Secretary Yvette Cooper has recently tabled plans to reduce judges' powers to prevent deportations with new "common sense" rules to clarify how judges interpret Article 8 of the ECHR. The plans come as leaders from calling on judges to reinterpret the article, to allow the expulsion of "criminal foreign nationals".