A fiery Saddam was back in court on Monday after boycotting his trial, but said he was forced to appear.
As soon as he arrived in court, Saddam roared: "Down with the traitor, down with traitors, down with Bush... long live the ummah (Islamic nation) ... long live the ummah ... long live the ummah..."
"I was forced into the courtroom," the former president of Iraq told Raouf Abdel Rahman, the chief judge.
Saddam, who condemns the court as an imperial creation of US military occupation, slammed his fist on the railing of his metal pen as he berated the chief judge.
"You don't have the right to sit on that chair because you are ignorant of the law," Saddam told Abdel Rahman.
The toppled Iraqi leader refused an offer of court-appointed lawyers to replace his defence team, which walked out of the court last month to protest against the tough new chief judge.
Saddam appeared with his seven co-accused, but he and his half-brother Barzan al-Tikriti quickly went into attack mode.
Barzan, his half-brother and former secret police chief, frequently interrupted the session as guards were seen pushing him down into his seat in the dock.
The trial has moved to its second phase, from victims testifying about abuses of security forces to witnesses, including government officials, shedding light on the events of that period.
"I was forced into the courtroom"
former president of Iraq
Two of Saddam's former senior aides told the chamber they were forced to appear as witnesses and one of them accused the chief prosecutor of being a former member of Saddam's intelligence services, throwing a new twist into a chaotic trial.
They told the court that they had been forced to appear as witnesses, reinforcing concerns by some human rights groups that a fair trial is impossible in Iraq.
Hassan al-Obeidi, intelligence director from 1980 to 1991, and Ahmed Hussein Khudayer al-Samarrai, the former head of Saddam's office, had been in detention and said they did not want to testify.
Al-Samarrai said he was blindfolded and handcuffed when he was brought to the court.
"I was brought here by force and I refuse to testify," al-Samarrai told the court. "I did not accept to be a witness."
Prosecutors hope former senior officials who served under Saddam will help them establish a chain of command that proves the former leader was directly involved in atrocities.
'Law of the jungle'
The appearance of Saddam was a surprise, given that a senior defence lawyer had told reporters earlier on Monday that all the defendants planned to continue boycotting the hearings.
Saddam and his defence lawyers walked out of the court on 29 January in protest at the new presiding judge's decision to expel Barzan for being disruptive.
"No international law can force people to attend trials"
head of Saddam's defence team
Khalil al-Dulaimi, the head of Saddam's defence team, said: "No international law can force people to attend trials.
"Unless you change the law and turn it into the law of the jungle."
The trial has frequently descended into farce, with sessions featuring long outbursts or walkouts by the defendants and their counsel, as well as the resignation of the previous chief judge.
Before Monday's session, al-Dulaimi said the defence team had conditions that had to be met to ensure their return, including replacing Abdel Rahman and Jaafar al-Mussawi, the prosecutor.
He also called for improved security for the defence counsel and continuous television transmission of the trial without periodic cuts to ensure that it was "transparent and fair".
Al-Dulaimi, who calls the entire court illegitimate, said the proceedings were dangerously adrift.
"They don't know what to do, because for a court you need a judge, a prosecutor, defence and defendants - if two of them are not here, then there is no more court," he said.
All eight defendants face the death penalty if convicted over the massacre of more than 140 Shias after an attempt on Saddam's life in 1982 in the town of Dujail.
They pleaded not guilty on the first day of the trial in October.