An Australian judge has frozen the assets from a book written by former Guantanamo Bay inmate David Hicks about his incarceration at the U.S. terrorist detention center.

The government is seeking to seize profits from Hicks' autobiography under a law that forbids convicted criminals from making profits from their crimes, including books or movie deals. But his lawyers say the law does not apply to Hicks, because he pleaded guilty before a U.S. military commission which they say was illegitimate.

New South Wales Justice Peter Garling issued a restraining order Wednesday against two assets related to the book, Guantanamo, My Journey.

Supporters of Hicks gathered outside the courthouse in Sydney to protest the freeze, many carrying copies of the autobiography. Greens Party lawmaker David Shoebridge accused authorities of using the case to warn people not to speak out against the government.

Hicks, a former Outback cowboy known as the “Aussie Taliban,” spent more than five years at the U.S.-run facility in Cuba after being captured in 2001 in Afghanistan. He was sent back to Australia in 2007 to serve out his sentence after admitting to providing material support for terrorism.

His father, Terry, says his son is suffering from post-traumatic stress disorder from his time at Guantanamo Bay.

His autobiography has sold more than 30,000 copies.