The Dáil’s Committee on Procedures and Privileges is to meet today to prepare its defence to a challenge brought by businessman Denis O’Brien.

The committee has hired senior counsel Sara Moorhead and barrister David Fennelly to assist its legal team in compiling its defence.

Mr O'Brien has initiated legal proceedings against the committee and has named every member, including the Ceann Comhairle Seán Barrett, in a submission to the High Court.

The committee has not met to discuss the proceedings since the members received notice of the case in early August.

Mr O'Brien decided to sue the committee after it ruled that Social Democrat TD Catherine Murphy and Sinn Féin TD Pearse Doherty had not abused privilege when they made claims against him in the Dáil.

In proceedings before the High Court, he is seeking a declaration that the 10 TDs on the committee are guilty of an “unwarranted interference with the operation of the courts and have caused or permitted a breach” of his constitutional rights.

He said article 40.31.1 of the Constitution guaranteed to respect, defend and vindicate the personal rights of the citizen.

The businessman said the decision by Ms Murphy and Mr Doherty to make allegations against him in the chamber was an attempt to “determine in whole or in large the case pending before the courts against RTÉ”.

He had been pursuing a High Court injunction against RTÉ preventing it from broadcasting a report about his personal banking arrangements with the Irish Bank Resolution Corporation.

The case has been listed for mention on October 7th in the High Court.