RTÉ Director General Cathal Goan has acknowledged that initial examination of the material contained in the programme High Society was 'less than it should have been'.
Mr Goan is being questioned by members of the Joint Oireachtas Communications Committee about the making of the programme, which was based on the book of the same name by Justine Delaney-Wilson.
However he insisted that the weight of evidence in the RTÉ Authority report on the programme showed that overall, the programme was true.
RTÉ's Managing Director of Television, Noel Curran, told the committee that the identity of the politician referred to in the programme was not known.
Mr Goan said 'there was now no recording' in existence.
Mr Curran also said the station's internal report on the programme criticises and puts hands up completely in terms of 'our editorial control before broadcast'.
He said that since broadcast of the first programme the station had gained access to the remaining seven hours of tapes.
'We interrogated the commissioning editors, spoke at length to the author, we received additional assurances from the publishers and their legal representatives that they had viewed contemporaneous notes of the remaining interviews, which constituted 18% of what was broadcast in the programme.
'82% of what was broadcast in the programme constituted the taped material, expert analysis and presenter analysis,' he said.
Mr Curran also told the committee he had no reason to doubt that all testimonies in the programme were true.
Pressed by Labour TD Liz McManus on the issue, he said RTÉ believed them to be true.
Shortcomings not endemic - RTÉ Chair
Yesterday, the station accepted there were shortcomings in the editorial process surrounding the making of the programme.
However following the completion of an internal report, RTÉ Authority Chairperson Mary Finan said the shortcomings were not endemic across factual programming in RTÉ.
She said a number of steps would be taken to ensure this would not happen again, including putting on hold the making of any factual programmes that are largely dependent on anonymous contributors and re-enactments, and the introduction of new guidelines for any programme that relies heavily on an external publication as its primary source.
Ms Finan (right) also said she was not aware of the identity of the politician mentioned on the programme. However she said the publishers of the book say they do know the identity of the individual, and that RTÉ accepts this.
Details of the internal report are now being discussed in Leinster House.
