GARDA Commissioner Noirin O'Sullivan has said journalists' phones are not being monitored by gardai.
The garda boss has also defended the role of her husband investigating alleged leaks of information to journalists.
Detective Superintendent Jim McGowan is one of two senior gardai leading the investigation.
A Garda superintendent has already been arrested and questioned as part of the probe.
"It is a matter of public record that my husband is a detective superintendent and any role that he carries out in An Garda Siochana is in that capacity," she said.
Ms O'Sullivan emphatically rejected suggestions gardai were now monitoring Irish journalists' phones.
"Absolutely not," she said.
"The relationship between the Garda Siochana and the media is very important.
"We very much respect the role of journalists and the role of the media in making sure that the public interest is best served."
She said the new TRUST initiative aims to enhance and protect the relationship between gardai and the media. The garda probe is understood to involve a seven-strong team based in Dublin.