In legal papers released as Assange appeared before a district judge at Woolwich Crown Court in South London, his lawyer Geoffrey Robertson said 39-year-old Assange would be taken to US against his will if extradited to Sweden.
Assange was accused of assaulting two women on separate occasions during a stay in Sweden last year and raping one of the women. He was questioned by police and denied the allegations, saying he had had consensual sex with both women.
Arguing on behalf of Assange, Robertson said, "There is a real risk his client faces further extradition or illegal rendition to the United States if he is sent to Sweden to answer allegations of sexual assault."
Contesting his extradition to Sweden, Assange's lawyer said if the WikiLeaks founder was "rendered to the USA, without assurances that the death penalty would not be carried out, there is a real risk he could be made subject to the death penalty, which is provided for in the Espionage Act."
"It is well known that prominent figures have implied, if not stated outright, that Assange should be executed," Robertson argued.
Lawyers for Assange have asked the Australian government to request assurances from their Swedish counterparts that he would never be removed from their country. They are concerned the Swedes could "bow to US pressure" or "naively" rely on diplomatic assurances and allow Assange to be taken across the Atlantic.
In an unusual move, Assange's legal team released a 74-page outline of their arguments against his extradition, as a two-day hearing got under way on Monday. The lawyers focused on the status of Swedish officials, the validity of the European Arrest Warrant and claims that his human rights would be breached.
Robertson argued that the Swedish prosecutor Marianne Nye is "not eligible" or an appropriate "judicial authority" to issue a EAW for his client, the Swedes are guilty of an "abuse of process" as they have not demonstrated any intention to charge or prosecute Assange and he cannot be extradited for questioning alone.Robertson said the application for a EAW is "disproportionate" as he is willing to co-operate and be interviewed by phone, email or video link. "The arrest warrant paperwork is not valid as it does not unequivocally state that he is wanted for prosecution and has been mistranslated," he argued.