Former Fine Gael strategist and Rehab director Frank Flannery has ruled out taking legal action against the Dáil's spending watchdog.
Mr Flannery was critical of the way he was treated by the Public Accounts Committee (PAC) during its investigation into the Rehab Group last year.
He said he found out that the Standards in Public Office Commission (Sipo) has no authority to examine the PAC's activities.
"My intention was that I would try and get the Dáíl processes to try and deal with problems and I still hope that that might happen. I don't intend to take legal action," he said.
Mr Flannery also said that absolute parliamentary privilege could be used to "trample" on the rights of citizens.
He was speaking on RTÉ Radio.
He said Denis O'Brien's decision to sue members of the Dáil's Committee on Procedures and Privileges (CPP) raised "legitimate issues".
Mr Flannery said he did not want to see parliamentary privilege curtailed, but argued that it should be subject to tighter regulation within the Dáil.
Mr O'Brien on Saturday defended his decision to take legal action against the CPP for what he said was its failure to investigate comments made about him under privilege in the Dáil chamber.
"I respect Dáil privilege as long as it is not exploited," he said.