WikiLeaks founder Julian Assange would be tried behind closed doors in a "flagrant denial of justice" if extradited to Sweden over sex crime allegations, his lawyer told a British court on Monday.
The 39-year-old Australian appeared at Belmarsh Magistrates' Court in southeast London at the start of a two-day hearing.
Swedish prosecutors want to question the whistleblowing website's chief over allegations of sexual assault and rape made by two women, but Assange claims the moves are politically motivated.
His lawyer Geoffrey Robertson said in his opening arguments that a rape trial in Sweden would violate Assange's human rights.
"He would be tried behind closed doors in a flagrant denial of justice," he told a packed courtroom at Britain's highest-security court complex.
"The Swedish custom and practice of throwing the press and public out of court when rape trials begin is one that we say is blatantly unfair, not only by British standards but also by European standards," Robinson added.
Assange's lawyers were also expected to argue that the extradition request is unacceptable because he has not been charged with any crime.
Wearing a dark blue suit and tie, the former computer hacker spoke only to confirm his name and date of birth as proceedings began.
A decision is not expected Tuesday, with the judge expected to defer his ruling until later this month.
If it goes against Assange he will be able to appeal all the way to England's supreme court.
Assange, who has won worldwide notoriety for his website's release of thousands of secret US diplomatic cables, insists his real fear is that Washington will try to persuade Sweden to pass him on to US authorities.
His lawyers will argue that Assange could face the death penalty if sent to the United States.
Robertson claimed that any trial in Sweden would be held "in secret" and that he would be held "without bail in conditions that have been condemned by the European Commission".
He also argued that the rape charge would not count as rape under European law.
"The court cannot accept the charge of rape is correctly identified, that that box has been ticked, because what is rape in Swedish law does not amount to rape in any other country," he said.
"The prosecutor describes this charge as "˜minor rape'. That is a contradiction in terms, rape is not a minor offence."
The three molestation charges relating to Assange's other accuser were also "plainly wrong" because the woman had consented to sex, he told the court.
The WikiLeaks chief, who was arrested in London in December 7, faces a widening criminal probe in the United States and has made powerful enemies in Washington.
He was released on bail a week after his arrest and has been staying at a supporter's country mansion under strict conditions including that he obey a curfew, wear an electronic tag and report to police daily.
Leaked details have cast new light on the rape and molestation accusations he faces after Swedish police reports filled with graphic details of the allegations reached the Internet last week.
The police documents, viewed by AFP, contain a statement from the alleged rape victim alleging that Assange forced himself on her, without wearing a condom, while she was asleep.
After a brief discussion, she allowed the intercourse to continue.
The documents also include a forensic report on the condom used during a sexual encounter with Assange's other alleged victim, who accused him of having deliberately broken the prophylactic.
The report says the condom had not been cut with scissors or a knife.
After releasing hundreds of thousands of confidential US documents about the wars in Iraq and Afghanistan last year, WikiLeaks has in recent months been slowly publishing more than 250,000 leaked US diplomatic cables.