Julian Assange has been denied permission to appeal against the High Court’s decision in December 2021 to extradite him to the US, Britain's Supreme Court confirmed.
The UK’s highest court on Monday said senior judges had rejected Assange’s bid to challenge the decision as his application did not raise “an arguable point of law”.
Assange’s legal team had previously said other parts of his appeal had not yet been heard by the High Court.
Assange, 50, is wanted in the US over an alleged conspiracy to obtain and disclose national defence information after WikiLeaks’ publication of hundreds of thousands of leaked documents relating to the Afghanistan and Iraq wars.
US authorities brought a High Court challenge against a ruling in January by then-district judge Vanessa Baraitser that Assange should not be sent to the US, in which she cited a real and “oppressive” risk of suicide.
After a two-day hearing, Lord Chief Justice Lord Burnett, sitting with Lord Justice Holroyde, ruled in favour of the US last year.
The senior judges found that Judge Baraitser had based her decision on the risk of Assange being held in highly restrictive prison conditions if extradited.
US authorities later gave assurances that Assange would not face such strict measures either before trial or post-conviction unless he committed a subsequent act for which they were warranted.
Lord Burnett previously said that if the original judge had been given those assurances at the time of her ruling, “she would have answered the relevant question differently”.
The WikiLeaks founder’s lawyers had sought to appeal that decision at the Supreme Court, arguing that it raised “serious and important” legal issues.
In January, Lord Burnett refused permission for the appeal and said the decision of whether to hear the appeal was up to the Supreme Court.
In her ruling that blocked the extradition in January 2021, Judge Baraitser found in favour of the US on all issues except for Assange’s mental health.
