The US government has urged the Supreme Court to overturn a ruling blocking the transfer of terror suspect Jose Padilla from military to civilian custody.
Jose Padilla, a US citizen, was arrested in Chicago in May 2002
An appeals court last week accused the government of trying to prevent full legal scrutiny of Mr Padilla's case by seeking his transfer to another court.
Government lawyers accused the appeals court of overstepping its authority.
Lawyers for Mr Padilla, a US citizen held as an "enemy combatant", want the Supreme Court to review his detention.
Mr Padilla was held without charge for more than three years after returning to the US from Pakistan in May 2002.
The former Chicago gang member who converted to Islam was initially accused of planning to attack the US with a crude radioactive device, or "dirty bomb".
He was finally charged in November this year with planning to undertake a "violent jihad" against the US by financing militants overseas.
No mention was made of the alleged "dirty bomb" plot among the charges eventually brought against him.
His lawyers have called on the Supreme Court to make a thorough inquiry into his detention and into the broader US policy of detaining alleged "enemy combatants" without trial.
An appeals court last week rejected the government's attempt to move Mr Padilla to civilian jurisdiction.
Judge Michael Luttig said the government's efforts "have given rise to at least an appearance that the purpose of these actions may be to avoid consideration of our decision by the Supreme Court".
The government had argued that transferring Mr Padilla to a civilian prison would mean his appeal to the Supreme Court over his indefinite military detention was no longer relevant and should be dismissed.
In their appeal to the Supreme Court on Wednesday, government lawyers attacked the appeals court's decision last week.
They described the decision as a "mischaracterisation of events and an unwarranted attack on the exercise of executive discretion".
The court, they said, had exercised "an unidentified and unprecedented judicial authority to disregard a presidential directive to transfer an enemy combatant out of military custody".