Gary McKinnon has refused to undergo tests at the hands of a medical expert appointed by the Home Office to see if he is a suicide risk if extradited to stand trial in the US.
McKinnon's legal team said professor Thomas Fahy, who was appointed to carry out the assessment, is not suitably qualified to judge the state of McKinnon's Asperger's Syndrome.
The team also noted the government had been told by The National Autistic Society that he was not a suitable expert. High Court judges had also urged the government to select a relevant authority to carry out the examination.
McKinnon has already been assessed by six independent specialists prior to the meeting that was supposed to take place on Thursday. Three of the most recent hearings led by leading experts in the field of Aspergers concluding he was not fit for a trial and a suicide risk.
Gary McKinnon's mother, Janis Sharp, said the government should take these reports as clear evidence extradition was not appropriate and that a trial in the UK should prove adequate.
"The Home Office should accept the very clear and incontrovertible evidence provided by the country's leading psychiatric experts in this field. It's time to make the right decision and to end Gary's torment of extradition," she said.
"When he's fit and ready, as we have said all along, the CPS could try him in this country for his foolish acts that happened over a decade ago."
She also bemoaned the seemingly endless rigmarole around the case that has seen it drag on for over a decade.
"Gary has endured 10 years of mental trauma and has lost 10 years of his youth and we so need a good end to this", she said.
"I'm sure that Theresa May will do the right thing, and will make a just and compassionate decision now and allow Gary to begin to recover from a decade of trauma and to regain some of the life he has lost."
The plight of McKinnon is echoed in that of TVShack founder Richard O'Dwyer who also faces extradition to the US, despite a huge online protest lead by Wikipedia founder Jimmy Wales to reverse the decision.
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