Assange, founder of WikiLeaks, appears in extradition hearing before Britain’s Supreme Court

WikiLeaks founder Julian Assange appeared before Britain’s Supreme Court this afternoon, arguing through his lawyers that a Swedish warrant for his arrest on allegations of sex crimes was invalid, according to Reuters.

Today was the first of two days of hearings scheduled for an appeal against a decision by a lower court of February last year, which was upheld by the High Court in November, that Assange, 40, should be extradited.

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In announcing its decision in December to hear today’s arguments, the Supreme Court said the matter at issue — whether a prosecutor is a judicial authority — was of “great public importance.”

The hearings will not address the validity of the allegations against Assange, brought by two Swedish female former WikiLeaks volunteers, of sexual assault. Assange was arrested in December 2010 in Britain and has been held on modified bail conditions since then.

He has not yet been charged with a crime and denies the alleations, also accusing the Swedish legal system of bias and politicization and claims his prosecution serves the interests of the U.S., where authorities are investigating him and WikiLeaks on suspicion of espionage.

Assange’s arrest came shortly after he caused an international uproar by releasing hundreds of thousands of US diplomatic cables, many of them classified.

Assange did not speak in court today, according to Reuters, but his legal team argue that the arrest warrant issued against him was not overseen by a judge and is therefore invalid. In Sweden and in countries applying the so-called “civil law” legal system, prosecutors have limited judicial authority and can sometimes issue arrest warrants.

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The Guardian reported that Dinah Rose QC, acting on behalf of Assange, made this case before the seven-judge panel hearing the case. Under the 1957 European convention on extradition, she reportedly said, an impartial authority, not a prosecutor, must be the one to seek extradition.

Appearing on behalf of Sweden, Clare Montgomery QC, argued that by law prosecutors were required to show some degree of impartiality and that the term “judicial authority” was always intended to include prosecutors in some countries.

Montgomery appeared less confident than Rose and “came under harsher questioning,” according to The Guardian.

According to The Wall Street Journal, a crowd of supporters appeared outside the courthouse and sang a hymn as Assange arrived, unfurling a rainbow flag and hold a placard that read: “Don’t’ shot the messenger,”

A decision is due in the coming weeks, according to Reuters. If Assange is unsuccessful, he could be take his case to the European Court of Human Rights, further postponing extradition while the case is considered. Should the ECtHR decline to hear the case, Assange could be extradited to Sweden almost immediately.

The hearing is to continue tomorrow.

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