An Australian Federal Court has dismissed an appeal by former US Marine Daniel Duggan, clearing the way for his extradition to the United States, where he faces charges of illegally training Chinese military pilots more than a decade ago.

Federal Court Justice James Stellios rejected Duggan’s challenge on Thursday, ruling there was no jurisdictional error in the Attorney-General’s decision to approve the extradition.

The 57-year-old Duggan, a naturalized Australian citizen who renounced his US citizenship in 2016, was arrested by Australian Federal Police in New South Wales in October 2022. He has been held in maximum-security detention since then.

US authorities allege that between 2009 and 2012, Duggan worked as a flight instructor at the Test Flying Academy of South Africa, where he trained Chinese pilots, including in advanced combat techniques. A 2016 US grand jury indictment accuses him of violating American arms export control laws.

In 2024, then-Attorney General Mark Dreyfus formally approved Duggan’s extradition to the US. Duggan argued that extradition should be refused because the conduct alleged against him did not constitute a criminal offence under Australian law at the time — a key legal requirement known as dual criminality.

Justice Stellios dismissed that argument, stating: “I am not persuaded that the impugned decisions were infected by jurisdictional error. Therefore, the application must be dismissed.”

A spokesperson for current Attorney-General Michelle Rowland confirmed that Duggan will remain in custody until he is surrendered to US authorities.

Duggan’s wife, Saffrine Duggan, expressed disappointment at the ruling in an interview with the ABC. “The family was disappointed by the ruling but would consider its options,” she said. “Make no mistake: we will not give up.”

Duggan has 28 days to lodge a further appeal against Thursday’s Federal Court decision.

The case has drawn international attention due to its implications for Australia-US relations and concerns over the transfer of sensitive military aviation skills to China.