The cost to the state of the various tribunals and inquiries is approaching €500 million, the Oireachtas Public Accounts Committee has been told.

The money includes €65 million which will have been spent on the Moriarty Tribunal by the end of this year - with possible ongoing payments in dealing with challenges to the tribunal’s findings.

The Moriarty Tribunal, which inquired into the finances of former Taoiseach Charles Haughey and Fine Gael TD Michael Lowry, reported in 2011.

Secretary General of the Department of the Taoiseach Martin Fraser told the committee on Thursday he would prefer to see the money being spent on “prevention”, rather than inquiries.

“If I had €500 million, I could think of better ways to spend it,” Mr Fraser told the committee.

“I think we need to be very careful about setting up tribunals. There is no doubt whatsoever that commissions of investigation are clearly faster and cheaper than tribunals” he said.

Mr Fraser revealed that nearly €7.5 million has been spent so far this year on the Moriarty tribunal.

He said the Fennelly Commission inquiring into several controversies involving the Garda Síochána had cost €3.5 million and its work is concluded.

He said a number of investigations were ongoing including separate commissions of inquiry into the sale of the private company Siteserv by the IBRC; and “Project Eagle” which was Nama’s sale of Northern Ireland-linked loans to US company Cerberus, for €1.6 billion.

Mr Fraser also confirmed the Strategic Communications Unit “will not exist after July”.

He said the Strategic Communications Unit was set up by Government as a matter of policy and as an accounting officer he was “comfortable” with that.

However, he said he was uncomfortable with controversy which arose after the unit promoted the National Development Plan and the National Planning Framework, as “advertorials” in local newspapers across the State.

He told the committee he had come to the view that the unit had “damaged the trust” of members of the Dáil who “could be involved in a future Government” and so he had taken the decision to recommend it be wound down.

Mr Fraser told Social Democrat TD Catherine Murphy savings of €5 million had been targeted in terms of rationalising the dissemination of information.

He said there were at least 452 State-owned websites which should be brought in under government branding and with greater use of the new Government portal gov.ie.However, he said he believed those savings would be achieved as the process of addressing the issues would continue without the strategic communications unit.