The WikiLeaks founder, Julian Assange, will try to win his release from prison tomorrow, a week after being ordered to be held on remand as Sweden requested his arrest over allegations that he sexually assaulted two women.
But even if the judge at Westminster magistrates court in London grants Assange bail, he could still be held.
The Crown Prosecution Service, which will represent the Swedish authorities in the UK court, has the right to appeal against any bail decision. Usually the suspect would still be held in custody anyway until an appeal hearing.
Raj Joshi, a former head of the European and international division at the CPS, and an expert on extradition, said: "If they feel they have grounds for opposing bail, they would be duty bound to appeal that. He'll be held pending the appeal, and until it is decided. That hearing is usually held within 48 hours."
The chances of Assange going underground, given that his face was "plastered all around the world", were low, he added. "With a number of conditions, such as, maybe, a tag, it would be difficult to see why bail would not be granted."
The decision to oppose bail will be made by the Swedish authorities, with Britain's CPS merely representing their interests in at tomorrow's hearing. Speculation that the US could lodge an extradition request continued over the weekend, but it is regarded as highly unlikely any such request would be lodged tomorrow.
Baroness Kennedy, who has extensive experience in human rights, has joined Assange's defence team.
His case has stirred fresh controversy about European arrest warrants, which the Swedish authorities would use for his extradition. Baroness Ludford MEP, the Liberal Democrat European justice and human rights spokeswoman, claimed the arrest warrant system, which she said she supported, was being used by Sweden to carry out a fishing expedition. Sweden had yet to formally charge Assange with any offense.
In a letter to the Guardian, Ludford wrote that past cases showed that it was "not a legitimate purpose for an EAW to be used to conduct an investigation to see whether that person should be prosecuted".
Ludford added: "Normal cross-border cooperation on collection of evidence or interrogation of suspects called 'mutual legal assistance', using for example video-conferencing or a summons for temporary transfer of a suspect, should be used when more appropriate. I urge the UK courts to refuse to allow the Assange EAW to be a fishing expedition without a pending actual prosecution. EU rules should be properly respected so that the integrity of the European arrest warrant process is protected."
Ahead of the case, lawyers today visited Assange in Wandsworth prison, south London, where the 39-year-old is being held in the segregation unit.
The decision by the district judge Howard Riddle to remand Assange into custody was made despite the film director Ken Loach, the veteran journalist John Pilger, and the socialite Jemima Khan, offering sureties for him totaling £180,000. The judge had concluded that because of the "serious" nature of the allegations against Assange, his "comparatively weak community ties" in the UK, and the fact it was believed he had the financial means and the ability to abscond, there was a substantial risk he would fail to surrender to the courts.
The allegations about Assange were made by two women. The first complainant, known as Miss A, said she was the victim of "unlawful coercion" on the night of 14 August in 2009 in Stockholm. The court heard Assange was alleged to have "forcefully" held her arms and used his body weight to hold her down. The second charge alleged he had "sexually molested" her by having sex without using a condom. A third charge claimed Assange "deliberately molested" Miss A on 18 August.
A fourth charge, relating to a woman called Miss W, alleges that on 17 August, Assange "improperly exploited" a situation where she was asleep, to have sex with her without using a condom.
A poll by Comres for CNN revealed today that 44% of Britons believe the charges against Assange are an excuse to place him in custody so the US can prosecute him over the US embassy cable leaks. But the same number say he should be sent to Sweden for questioning.
Meanwhile a dating site profile from 2007, supposedly created by Assange, had prompted by some lively online debate. The profile on the OKCupid site featured pictures of Assange, though gave the name Harry Harrison - who described himself as a "passionate and often pig- headed activist intellectual" who sought to change the world. He concluded: "Write to me if you are brave."