Assange challenges extradition

Ben Emmerson QC, appearing for Assange, 40, told two judges the European arrest warrant (EAW) on which he was being held was flawed because it failed to provide "a fair, accurate and proper" description of the alleged sexual misconduct.

Mr Emmerson also argued Assange was a victim of a "philosophical and judicial mismatch" between English and Swedish law on what constituted sex crimes.

Assange says the allegations against him are politically-motivated, particularly after the WikiLeaks website published a mass of leaked American diplomatic cables that angered the US government.

He said nothing as he arrived at the court in London with lawyers today.

A handful of supporters gathered outside the entrance to greet him.

Assange hosted a lavish 40th birthday party at the weekend attended by celebrity guests and supporters.

Although not charged, the Australian computer expert is wanted by the Swedish prosecution authority to answer questions on three allegations of sexual assault and one of rape, said to have been committed in Stockholm last August. The accusations were made by two female WikiLeaks volunteers.

In a case which has drawn international interest, Justice Thomas and Mr Justice Ousely are being asked by Assange's legal team to rule that his sexual encounters with the women were "consensual" and the alleged offences are not extradition offences.

At a hearing in February, Judge Riddle dismissed all Assange's arguments that, if charged, he could not get a fair trial.

Assange has expressed fears that extradition to Sweden could be a stepping stone to being sent to the US to stand trial on fresh charges relating to WikiLeaks, and he could even face the death penalty.

If his High Court appeal is unsuccessful, he could take his case to the Supreme Court, the highest court in the land.

Assange, who won bail in December, has been staying at Ellingham Hall, the 10-bedroom Norfolk farmhouse owned by Vaughan Smith, director of the Frontline media club, which was the venue for his birthday party.

Bail conditions include having to wear an electronic ankle tag and check in daily at a nearby police station.

Mr Emmerson told the judges the allegations against Assange could not amount to crimes in England and therefore extradition must be blocked.

The extradition order was also flawed because it sought Assange's return to Sweden "not for prosecution but for the purposes of an investigation".

Mr Emmerson argued that using extradition for the limited purpose of an investigation amounted to a "a disproportionate utilisation" of the EAW system.

He stressed that the court was not inquiring into the credibility of the women - referred to as SW and AA - who had made complaints against Assange, or determining questions of guilt or innocence.

Nothing he said should be taken to involve any condemnation of the women.

It was not intended to challenge "the genuineness of their feelings of regret about having had consensual sex with Mr Assange or trivialise their experiences".

Nor was he challenging the fact that they "found Mr Assange's sexual behaviour in these encounters disreputable, discourteous, disturbing or even pushing towards the boundaries of what they were comfortable with".

But the sexual activities that occurred had taken place with consent and, unlike in Sweden, could not be criminalised in the English jurisdiction, argued Mr Emmerson.