Lawyers for a former fighter pilot fighting extradition to the US want an Australian federal agent to explain where they got information on which they based an erroneous "assumption". In an affidavit filed on Monday, the federal agent acknowledged the error when they alleged in an October filing that Daniel Edmund Duggan, 55, was the director of a company that he was not, saying they made an incorrect inference or assumption. Duggan's barrister Gregory Jones sought to cross-examine the federal agent on Wednesday in a bid to discover what information their error was based on. "You can only assume or infer from something that is conveyed to you, otherwise you're just making it up," Mr Jones told the court. Duggan was arrested at a supermarket car park in the NSW central west in October 2022 after a request from US authorities. The former US military pilot, who became an Australian citizen in 2012, is accused of breaching US arms trafficking laws by training Chinese pilots while working at a South African flight school in the early 2010s. The father of six denies the allegation. A foreign restraining order issued by a US court has interfered with the sale of a NSW south coast property owned by Duggan's wife in order to fund legal bills. His lawyers are seeking to have the order discharged, telling the NSW Supreme Court it was based on incorrect information. Barrister Greg O'Mahoney, acting for the Australian Federal Police commissioner, read a relevant portion of the affidavit to the court. "I seek to make clear I assumed or inferred incorrectly," he quoted. "This assumption I made was in error and I regret that it occurred." Mr Jones said the affidavit went to some lengths in a bid to satisfy the court it was an inadvertent error, but it still needed to be explained. "The court is entitled to know, what did he assume or infer from?" he said. Justice Nicholas Chen accepted Mr Jones' argument that there was legitimate forensic purpose to seeking source material and ordered its production on Wednesday morning. Mr O'Mahoney said documents were "being harnessed as we speak". Duggan's lawyers dropped a bid to access sensitive defence and intelligence reports in court on Friday after earlier saying they were key to demonstrating overtly political aspects of the US extradition request. Australian Associated Press