The Senate Committee on Intelligence is now conducting an investigation of the CIA's detention-and-interrogation programme. Also, Attorney General Eric Holder Jr could decide next week whether to appoint a criminal prosecutor to investigate the interrogation tactics, the Times reported.

Another development last week could challenge the Obama administration's continuing objections to allowing the questioning of high value prisoners at Guantanamo in cases involving other prisoners.

Judge Ricardo Urbina of the US District Court in Washington ruled that lawyers for a Pakistani prisoner at Guantanamo, Abdul Raheem Ghulam Rabbani, may question the alleged mastermind of the Sep 11, 2001 attacks, Khalid Sheikh Mohammed, who is also held at Guantanamo.

The prisoner, Abdul Raheem Ghulam Rabbani, is seeking to challenge his own detention.

The US government has for years been battling the courts over its refusal to allow the questioning of high level suspects out of fear top secret information could be revealed in the courtroom.

Under Bush, another man indicted for his role in the 9/11 attacks, Zacarias Moussaoui, precipitated a major court battle with his demands that Mohammed and other operatives held at Guantanamo be allowed to testify in his trial.

After the government defied a court order that they be available for questioning, the trial judge ruled out the death penalty in the case but an appeals court restored the option. The jury chose life imprisonment, and Moussoaui began serving his sentence in 2006.

Judge Urbina's order last week in the Rabbani case could add fuel to the pressure for habeas corpus by prisoners at Guantanamo. Habeas corpus is a key right in the US justice system that prevents prisoners from being held without charges being brought and a trial being held.