The former head of the Garda press office has denied telling a whistleblower of an alleged smear campaign involving senior officers.
Sergeant Maurice McCabe has claimed former Garda commissioner Martin Callinan composed hundreds of text messages for dissemination through his chief press officer Superintendent David Taylor to politicians and journalists.
The whistleblower said he was told the messages were to focus on an unfounded and false claim of sexual assault made against him in 2006.
At the Disclosures Tribunal, a lawyer for Supt Taylor said her client did not accept that he sent texts about the "scurrilous" untrue rumours of sexual assault.
Tara Burns BL said: "Text messages related to informing persons regarding any developments or media broadcast.
"The text messages did not relate to the rumours regarding you and the sexual assault allegation in 2006."
Sgt McCabe responded that it was his word against Supt Taylor's and stood by his account.
Ms Burns said: "Supt Taylor denies that he said that Martin Callinan created these texts and sent them on.
"He denies that they were in relation to specific malicious rumours in 2006."
Sgt McCabe claims he was harassed after making allegations of Garda wrongdoing.
The row over how senior Garda figures and ministers handled his claims of negligence and corruption almost brought down the Irish Government before Christmas.