The independent inquiry into the 1974 Dublin and Monaghan car bombings, which killed 33 people, will cost over €600,000, according to official figures released yesterday.
The commission of investigation into the bombings, headed by senior counsel Paddy MacEntee, was set up by the Government to examine elements of the Garda investigation.
An earlier inquiry by former High Court judge, Mr Justice Henry Barron, failed to produce an explanation over why the Garda investigation was to all extents and purposes concluded within months of the atrocity.
Mr MacEntee will also investigate the reasons, if any, behind the disappearance of some of the investigation paperwork from the Garda files, though many of the investigating officers are now dead.
In Iris Oifigiúil, it was stated that the investigation would cost an estimated €604,880 in legal fees, salaries and other administrative costs for six months - by which time it is due to report to the Taoiseach.
The inquiry has been asked to investigation why Garda detectives did not investigate information from members of the public about a white van, with an English registration plate, seen parked outside the Department of Posts and Telegraphs on Portland Row and then later seen at the B & I ferry port in Dublin.
In addition, Mr MacEntee has been asked to inquire into why the Garda did not properly investigate a man with alleged links to the Ulster Volunteer Force who stayed at the Four Courts Hotel from May 15th-17th, 1974.
The MacEntee investigation is the first to be established under the Commissions of Investigation Act 2004, which was designed to create less-expensive, speedy methods of inquiry. It was established in response to the recommendations of the Joint Oireachtas Committee on Justice, Equality, Defence and Women's Rights in its report of March 2004.