Legislation governing the Central Bank prevented it from passing on to the Department of Finance or the Office of the Revenue Commissioners information gleaned during its activities as a regulator.
Section 16 of the Central Bank legislation prevents it from disclosing information acquired in its regulatory role except in specific circumstances, such as to other regulators, in a criminal court of law or with the agreement of the institution.
Effectively, the legislation meant the bank was unable to share information about Guinness & Mahon's offshore activities with either the Revenue or the Department of Finance.
The bank was not in a position to take action itself. Because its main concern was with prudential supervision, it could not impose sanctions, such as the withdrawal of a banking licence, on institutions it suspected of criminal activity.
It is only since the introduction in 1994 of legislation on money laundering that the bank has a duty to tell the Garda if it suspects an institution of involvement in crime.
A bank spokesman declined to comment on yesterday's revelations at the tribunal except to say that it had already made a written submission to the tribunal.