Saddam Hussein has accused Iraq's Interior Minister of killing and torturing thousands of people.
Interior Minister Bayan Jabor is a hate figure among Sunnis, who accuse him of waging a sectarian war against them and allowing Shia militias to run hit squads with impunity. He denies the accusations.
Chief judge Raouf Abdel Rahman and one of Saddam's lawyers, Bushra Khalil, had several heated exchanges during today's session. Ms Khalil was eventually ejected from the court.
Saddam Hussein is on trial in Baghdad with seven others for the killing of 148 people in Dujail in July 1982.
His appearance came a day after the court announced that he would face new charges of genocide and crimes against humanity.
The new indictments relate to a military campaign against Kurdish communities in northern Iraq in the late 1980s in which as many as 180,000 people may have died.
The trial continues tomorrow.
Separately, in Iraq, the interim Prime Minister, Ibrahim al-Jaafari, has rejected growing pressure on him to resign, saying Iraqis must be left to choose their leader democratically.
Mr Jaafari, who is a Shia Muslim politician, has rejected calls from opponents and some political allies to step aside to break a political deadlock over sharing power with Kurds and Sunni Muslims.
The US and Britain have said that Iraq's failure to appoint a new government four months after elections is undermining security.
