More than 540 suspects are being held at Guantanamo after being detained during the 2001 invasion of Afghanistan and in other operations in the US "war against terrorism." They are al Qaeda suspects and accused Taleban fighters.
Bush administration attorneys argued the prisoners have no constitutional rights and their lawsuits, challenging the conditions of their confinement and seeking their release, must be dismissed.
The tribunals, formally called a military commission, at the base were authorised by President George W. Bush after the September 11, 2001, attacks, but have been criticised by human rights groups as being fundamentally unfair to defendants.
Green's 75-page opinion was the unclassified version made available for public release. It stemmed from 11 cases involving Guantanamo prisoners.
Her ruling probably will not be the final word on the issue. A different federal judge in Washington, D.C, on January 19 dismissed the cases of seven Guantanamo prisoners on the grounds that they have no recognisable constitutional rights and are subject to the military review process.
The cases could be appealed to the US appeals court, and then ultimately to the US Supreme Court.