A British computer expert will launch a new legal battle today to avoid extradition on charges of hacking into US military networks.
Lawyers for Gary McKinnon, from Wood Green, north London, say he would be at real risk of psychosis or suicide if removed to America.
Mr McKinnon, who began writing his own software programmes at 14, was diagnosed last August as suffering from Asperger's syndrome.
It was not an issue taken into consideration when the Home Secretary gave the go-ahead for extradition last October.
Today Lord Justice Stanley Burnton and Mr Justice Wilkie, sitting in London, will be asked to rule on whether the health risk is too great to allow removal.
Mr McKinnon could face a lifetime in jail if he is found guilty in the US of sabotaging vital defence systems after the September 11 terror attacks.
His supporters say he acted through "naivety" as a result of Asperger's - a form of autism which leads to obsessive behaviour - and should not be considered a criminal.
His lawyers have fought a series of battles to block his removal.
They lost every one until earlier this year when two senior judges ruled that the fresh evidence about his health "merits substantive consideration".
Previously his case had been rejected on other grounds by a district judge, the High Court and then, in July last year, the House of Lords. The European Court of Human Rights in Strasbourg also refused to intervene.
Now his legal team says expert evidence shows that extradition could create anxiety leading to psychosis and suicide.
The US government has accused Mr McKinnon of being a cyber-terrorist responsible for the "biggest military hack of all time", involving 97 government computers belonging to organisations including the US Navy and Nasa.
Mr McKinnon has admitted hacking into the system in 2001-2, but claims that he was looking for evidence of extra-terrestrial life.
He was caught as he tried to download a grainy black and white photograph which he believed was an alien spacecraft from a Nasa computer housed in the Johnson Space Centre in Houston, Texas.
Mr McKinnon was easily traced by the authorities because he used his own email address.
He has always said that he had no malicious intent but was looking for classified documents on UFOs which he believed the US authorities had suppressed.
He has signed a statement accepting that his hacking constituted an offence under the UK's Computer Misuse Act 1990.
He and his family hope that, if there is a trial, it will be in the UK.Reuse content