Julian Assange extradition appeal at supreme court Julian Assange outside the high court in London on 5 December 2011. Photograph: AFP/Getty Images 9.09am: Julian Assange, the founder of WikiLeaks, is today taking his case against extradition to Sweden to the supreme court. This is his last chance to avoid extradition to face allegations of rape and sexual assault relating to a trip to Sweden in 2010. In February last year, a court ruled he should be sent to Sweden to answer the accusations against him; he appealed and lost. The supreme court justices are being asked to rule on the specific question: does a prosecutor have sufficient authority to require someone's extradition? In Britain generally only judges can approve arrest warrants. But the warrant for Assange was issued by Sweden's public prosecutor. Assange's lawyers argue that the Swedish system is unfair because it puts the power to issue arrest warrants in the hands of the same prosecutors who are trying to put him in jail. As my colleague Esther Addley noted in this very informative piece, many legal observers were surprised when the supreme court not only agreed to hear Assange's petition, but said seven judges rather than the usual five would preside, "given the great public importance of the issue raised." Julian Knowles QC, a barrister specialising in extradition law based at Matrix Chambers, said the decision to might be more easily explained by the enormous public interest in Assange's case - "to send the message that the highest court in the land has looked at this case, and it's had the attention of the best legal minds in the country." In Knowles's view, the law in this area - whether a public prosecutor is a valid judicial authority - has been comprehensively tested. This point has been litigated before, and the courts have always reached the clear answer that while it may look odd to English eyes, common law eyes ... European systems don't have the same structure. The courts have always said that to make extradition work, you have to be flexible in your approach to what extradition is. The consequences if Assange were to win, he said, would be "very profound." It would basically mean, until the law is rewritten, that extradition to Europe [would] become very difficult, if not impossible. Because in the vast majority of European extradition requests, the arrest warrant is issued not by a court, as it would be in England, but by a prosecutor. It is much easier to predict what will happen if Assange loses. Though he would still have the option to make an application to the European court of human rights (as he has hinted he may do at earlier stages of the process), this would not delay his extradition, since Sweden is also a signatory to that convention. Assange would probably be kept in custody - bail does not exist in Sweden - and if he is charged a trial might begin in a few months. The case is set to begin at 10.30am and to last for two days. The judges' decision is then expected in matter of weeks. Footage of the proceedings will be streamed live here. (The supreme court has permitted the televising of all its proceedings since it opened two years ago. Adam Wagner has looked at the implications of that here.) Comments have not been switched on on this blog for legal reasons.