A Senior Counsel is to be appointed to examine the claims of Garda misconduct given to the Taoiseach last week.
The decision was made at the Cabinet meeting this morning .
Sergeant Maurice McCabe gave the dossier to Fianna Fáil leader Micheál Martin, who passed it to Enda Kenny.
It contained claims of Gardaí failing to properly investigate serious crimes, including a murder.
Ministers decided to appoint the barrister after getting a report on the claims, and hearing from the Minister for Justice on the Department's responses to Sergeant McCabe.
In a statement this afternoon, Fianna Fáil expressed "incredulity" at the response of the coalition, saying the Cabinet should have decided to hold a proper independent inquiry.