GARY McKinnon's parents are preparing to take their legal fight to the House of Lords to stop their son being extradited to the US, the Ham&High has learned. Wilson Sharp and his wife Janis have until September 14 to prepare a case on why

Charlotte Newton

GARY McKinnon's parents are preparing to take their legal fight to the House of Lords to stop their son being extradited to the US, the Ham&High has learned.

Wilson Sharp and his wife Janis have until September 14 to prepare a case on why Mr McKinnon - who has Asperger's syndrome - should be allowed to appeal to the Supreme Court, the new name for the judicial functions of the House of Lords.

They plan to use the European Convention on Human Rights to argue for Mr McKinnon's right to humane treatment and say family life would be breached if he were extradited and tried in the US.

Mr Sharp spoke out after his stepson lost his latest bid at the High Court on Friday to avoid extradition on charges of hacking into US security and defence computer networks. "Gary is in a very bad state mentally," Mr Sharp said. "He's been okay up until now but Friday's decision was a step too far. He's extremely anxious, he's not talking."

The US wants to try Mr McKinnon, 43, a former pupil of Highgate Wood School, for what it alleges is the "biggest military computer hack of all time". He is accused of getting into 97 US army, navy, Nasa and Department of Defence computers after 9/11, and leaving the network vulnerable to intruders in 2001 and 2002. Mr McKinnon was living with his girlfriend in Hillfield Avenue, Hornsey, at the time.

He admits hacking but denies it was malicious or that he caused $800,000 damage, and has always maintained he was searching for classified documents on UFOs.

Mr McKinnon had asked the court to rule on whether his Asperger's syndrome means he cannot be extradited to the US. His lawyers argued extradition is "unnecessary, avoidable and disproportionate" and has not taken place in other cases.

But Lord Justice Stanley Burnton and Mr Justice Wilkie said on Friday extradition was "a lawful and proportionate response to his offending". Forty MPs have signed a letter calling for President Obama to intervene. They argue Mr McKinnon should be tried in the UK and the Anglo-US extradition treaty signed in 2003 by the then home secretary David Blunkett was unfair. Pressure is mounting on the government to stop the extradition.

But Home Secretary Alan Johnson told the Ham&High: "It would be illegal for me to stop the extradition of Gary McKinnon, which the court ruling has made clear. He is accused of serious crimes and the US has a lawful right to seek his extradition."

Lynne Featherstone, Liberal Democrat MP for Hornsey and Wood Green, said: "This case highlights just how unfair the extradition rules are between the US and Britain. The Government should stop his extradition."

Cllr Claire Kober, leader of Haringey Council, said: "The American authorities must take into account his particular circumstances and provide appropriate assurances regarding his detention. As such I have written to the Home Secretary to ensure safeguards are in place.