A military judge has agreed that the defence team of a soldier accused of abusing Iraqi prisoners should be allowed to question top US generals.
Sgt Davis's lawyer tried to have Bush and Rumsfeld summoned
He ruled that the head of US-led forces in Iraq, Lt Gen Ricardo Sanchez, and other senior officials could be summoned as witnesses.
The judge also said the Abu Ghraib jail where the abuse took place was a crime scene, and so could not be destroyed.
The rulings came at a hearing into the cases of three men on abuse charges.
They are Charles Graner, Ivan Frederick and Javal Davis.
Jeremy Sivits: Sentenced to a year in jail
Charles Graner, Ivan Frederick and Javal Davis: Before a Baghdad hearing
Lynndie England: To face a US hearing
Sabrina Harman and Pte Megan
Ambuhl: No decision yet on courts martial
One soldier, Jeremy Sivits, has already been sentenced to a year in jail, but this trio face more serious charges and sentences of up to 24 years.
Monday's initial hearing in Baghdad was intended to resolve any legal technicalities before they face a full trial.
At Monday's session, the judge, Col James Pohl, postponed Staff Sgt Frederick's pre-trial hearing until 23 July, after his civilian lawyer failed to appear in person.
One of the defence lawyers made an unsuccessful effort to seek testimony from US President George W Bush and Defence Secretary Donald Rumsfeld.
Civilian defence counsel Paul Bergrin - who represents Sgt Davis - accused Mr Bush and Mr Rumsfeld of sidestepping the Geneva Convention in their "war on
terror", and said his client was instructed on a daily basis to "soften up" Iraqi prisoners to obtain intelligence.
However, his request was rejected by Col Pohl.
Specialist Graner has been accused of striking several detainees by jumping on them as they lay in a pile on the floor.
He is also charged with stamping on the hands and bare feet of several prisoners, and punching one inmate in the temple so hard that he lost consciousness.
Sgt Frederick is accused of forcing prisoners to masturbate, placing naked detainees into a human pyramid and placing wires on a hooded detainee's hands, telling him he would be electrocuted if he fell off a box on which he was forced to stand.
The charges relate to some of the most notorious incidents
A photograph of the incident was one of the most widely circulated when the abuse scandal first came to light at the end of April.
Sgt Davis is accused of maltreating prisoners, stamping on their hands and feet and putting detainees in a pile on the floor to be assaulted by other soldiers.
Seven soldiers in all have been accused of abusing Iraqi detainees.