Ali al-Marri was arrested three months after the 9/11 attacks
The US Supreme Court has agreed to rule on whether a man suspected of terrorism can be held in prison indefinitely by the government without being charged.
Ali al-Marri, from Qatar, has been in solitary confinement in South Carolina since 2003.
He is the only person held in the US as an enemy combatant - a designation that has no international legal definition.
The case is seen as a test of the expanding executive powers introduced under President George W Bush.
Mr al-Marri's lawyers, who made an appeal in July, argue that Mr Bush disregarded American legal principles.
Although Congress gave the president power to detain him as part of its authorisation for use of military force after the 9/11 attacks in 2001, the lawyers said it did not permit indefinite military detention of a person lawfully residing in the US, without criminal charges or a trial.
The American Civil Liberties Union (ACLU), which represents Mr al-Marri welcomed the Supreme Court's decision to review the case.
The ACLU's Steven Shapiro said he hopes the court would "ensure that people in this country cannot be seized from their homes and imprisoned indefinitely simply because the president says so".
Government lawyers had failed to persuade the Supreme Court to reject Mr al-Marri's appeal without hearing the case.
The Supreme Court will hear the appeal in March
The administration argued that the case should go to federal district court in South Carolina, instead of the Supreme Court.
The Supreme Court will hear the case in March, with a decision expected by the end of June.
Mr al-Marri entered the US on a student visa on 10 September, 2001, and was arrested three months later as part of the FBI investigation into the terror attacks.
He pleaded not guilty when he was indicted in Illinois for credit card fraud, making false statements to the FBI and other charges.
After the government dropped the criminal charges in June 2003, President Bush designated him an enemy combatant.
Only two others have been held as enemy combatants inside the US since 9/11.
In January 2006, Jose Padilla, held for three years, had his case transferred to a criminal court in Miami, where he was later convicted on charges of offering his services to terrorists.
Yaser Esam Hamdi, another US citizen held for two years, was deported to Saudi Arabia after the Supreme Court in 2004 upheld his right to challenge his detention.