The Taoiseach has received harsh criticism from Opposition parties in the Dáil, recalled to debate the contents of the Flood tribunal's second interim report.
The Fine Gael leader Mr Enda Kenny ysaid Mr Ahern's investigation of Mr Ray Burke was "a sham" and his handling of the affair had brought the "highest office to the lowest repute."
Mr Brendan Howlin of the Labour Party said no taoiseach in Irish history had "fallen from grace as quickly or as completely as Mr Ahern."
Earlier the Taoiseach told the Dáil he had not been mentioned in the Flood report and therefore had no questions to answer in relation to its contents.
The debate was adjourned and was due to resume at about 9.30. Time for the debate has been extended until midnight.
The House was recalled from its summer recess for the debate, which was delayed after clashes between the Opposition and the Government on the format it would take.
Opposition parties demanded the Taoiseach field questions on his appointment of Mr Ray Burke as Minister for Foreign Affairs in 1997. The Flood report published last month said Mr Burke received "corrupt" payments.
But the Government refused a question-and-answer session on the grounds that previous tribunal findings have never resulted in such debates.
During angry scenes Fine Gael's Mr John Deasy was dismissed from the House. Afterwards he said: "As I said in the Chamber before my dismissal, the Taoiseach's arrogance in refusing to answer questions, has lowered politics and the Dáil Chamber to an extent I never thought possible."
"It is obvious the Taoiseach and his ministers are afraid to answer questions," he added.