He obtained unpublished copies of the report in 2016
Paul Reynolds has told the Disclosures Tribunal he was not influenced by Garda Headquarters in preparing reports for RTÉ in May 2016.
The broadcaster's crime correspondent had obtained unpublished copies of the O'Higgins Commission Report, which he quoted from for his broadcasts.
The tribunal heard Maurice McCabe took issue with Mr Reynolds' coverage, which said he told a lie.
Mr Reynolds got leaked copies of the final report of the O'Higgins Commission - and broadcast several reports on it on May 9th 2016.
Asked if Noirin O'Sullivan had attempted to influence the RTÉ broadcasts, Mr Reynolds said that did not happen.
Mr Reynolds said he knew it was controversial to say that Maurice McCabe had told a lie, but he said the report said Sergeant McCabe had told an untruth - the dictionary definition of which was a lie.
Sergeant McCabe in his protected disclosure said the broadcasts referred to him as a liar and irresponsible.
Mr Reynolds said the word 'irresponsible' did not appear in either his or Judge O'Higgins' reports.
His evidence continues on Friday.