Lawyers for the American government are to tell a London court on Wednesday why they think Julian Assange should face espionage charges in the United States, in response to a last-ditch bid by his defense to stop the extradition of the WikiLeaks founder.

Assange’s lawyers are asking the High Court to grant him a new appeal — his last legal roll of the dice in the long-running legal saga that has kept him in a British high-security prison for the past five years.

The 52-year-old Australian has been indicted on 17 charges of espionage and one charge of computer misuse over his website’s publication of classified U.S. documents almost 15 years ago. American prosecutors say Assange helped U.S. Army intelligence analyst Chelsea Manning steal diplomatic cables and military files that WikiLeaks later published, putting lives at risk.

Lawyers for the U.S. have argued in written submissions that said Assange was being prosecuted “because he is alleged to have committed serious criminal offences.”

Attorney James Lewis said Assange’s actions “threatened damage to the strategic and national security interests of the United States” and put individuals named in the documents — including Iraqis and Afghans who had helped U.S. forces — at risk of “serious physical harm.”

To his supporters, however, Assange is a secrecy-busting journalist who exposed U.S. military wrongdoing in Iraq and Afghanistan. They argue that the prosecution is politically motivated and he won’t get a fair trial in the U.S.

Assange’s lawyers argued on the first day of the hearing on Tuesday that American authorities are seeking to punish Assange for WikiLeaks’ “exposure of criminality on the part of the U.S. government on an unprecedented scale,” including torture and killings.

Lawyer Edward Fitzgerald said Assange may “suffer a flagrant denial of justice” if he is sent to the U.S.

Assange’s lawyers say he could face up to 175 years in prison if convicted, though American authorities have said the sentence is likely to be much shorter.

Assange was not in court on Tuesday because he is unwell, his lawyer said. Stella Assange, his wife, said Julian had wanted to attend, but was “not in good condition.”

Assange’s family and supporters say his physical and mental health have suffered during more than a decade of legal battles, including seven years in self-exile in the Ecuadorian Embassy in London and the last five years in the high-security prison on the outskirts of the British capital.

Stella Assange, who married the WikiLeaks founder in prison in 2022 — said last week that his health has deteriorated during years of confinement and “if he’s extradited, he will die.”

Supporters holding “Free Julian Assange” signs and chanting “there is only one decision — no extradition” held a noisy protest outside the neo-Gothic High Court building for a second day on Wednesday.

Assange’s legal troubles began in 2010, when he was arrested in London at the request of Sweden, which wanted to question him about allegations of rape and sexual assault made by two women. In 2012, Assange jumped bail and sought refuge inside the Ecuadorian Embassy.

The relationship between Assange and his hosts eventually soured, and he was evicted from the embassy in April 2019. British police immediately arrested and imprisoned him for breaching bail in 2012. Sweden dropped the sex crimes investigations in November 2019 because so much time had elapsed.

A U.K. district court judge rejected the U.S. extradition request in 2021 on the grounds that Assange was likely to kill himself if held under harsh U.S. prison conditions. Higher courts overturned that decision after getting assurances from the U.S. about his treatment. The British government signed an extradition order in June 2022.

Meanwhile, the Australian parliament last week called for Assange to be allowed to return to his homeland.

If judges Victoria Sharp and Jeremy Johnson rule against Assange, he can ask the European Court of Human Rights to block his extradition — though supporters worry he could be put on a plane to the U.S. before that happens, because the British government has already signed an extradition order.

The two justices could deliver a verdict at the end of the hearing on Wednesday, but they’re more likely to take several weeks to consider their decision.