Senior lawyers argue the conditions faced by a former US fighter pilot accused of aiding the Chinese military are impeding his case for bail.
Daniel Duggan is facing extradition to the United States, where he will face charges of violating arms export laws and money laundering, which he denies.
Mr Duggan has been remanded in NSW's Lithgow prison for the past seven months while he awaits the outcome of the extradition request.
The Australian section of the International Commission of Jurists wrote to the NSW Corrective Services Commissioner raising concerns about how Mr Duggan was classified as a high-risk detainee, with documents about the classification withheld.
The letter said without the information about why he was classified as high-risk, he couldn't properly prepare a bail application.
The jurists stated they remained concerned an Australian citizen was being treated as a danger to the community despite facing non-violent charges.
"We are also concerned that his right to a fair hearing of his bail application may be compromised by the actions taken," they wrote.
Mr Duggan's wife Saffrine said the prosecution showed that the Australian legal system was being "weaponised against an Australian citizen at the behest of a foreign government".
She said redactions from documents about the details of the case showed a lack of transparency within the system.
"Nothing in them explains why an Australian citizen and father of six Australian children needs to be locked up in maximum security solitary confinement for seven months, while he tries to defend himself," she said.
Mr Duggan has complained about a lack of basic materials to keep him warm but a Corrective Services NSW spokesman said all inmates are supplied with appropriate bedding and linen.
A letter from NSW Corrective Services Commissioner Kevin Corcoran responding to Greens senator David Shoebridge said he approved the downgrading of Mr Duggan's security classification from extreme high risk in mid-December.
He said the prison was assisting with family visits and ensuring phone contact has been maintained and that additional contact with his wife had been approved the week before his mother's funeral.
Mr Duggan's lawyers say the attorney-general needs to take greater oversight of the case after complaints were made to the Inspector-General of Intelligence and Security about his treatment and NSW Correctional Services about his conditions.
International criminal law expert Glenn Kolomeitz said any alleged inappropriate behaviour by intelligence and security agencies, or non-compliance with international human rights, were all matters for the federal attorney-general.
The attorney-general maintains the complaint to the inspector-general is a matter for Mr Duggan while prison conditions sit with corrective services.
Mr Duggan is a former US Marines naval aviator and flight instructor.
The US government says he "conspired with others to provide military training to the People's Republic of China relating to aircraft carrier approach and landing".
It's also alleged he provided military training to Chinese pilots in 2012 and conspired to launder payments for the services.
He has consistently denied the charges.
The Australian government is also working to strengthen its own national security laws in light of the case and revelations China had tried to poach Western military pilots.
A spokeswoman for Defence Minister Richard Marles said the government was working to put legislation in place to ensure there were no doubts about the obligations defence force personnel have to keep the nation's secrets.
There are a number of laws in place to prevent the sharing of national security secrets and providing military training.
