The Department of Finance first raised concerns in August about the confidentiality and privileged nature of some of the documents to the Commission of Investigation into the Irish Bank Resolution Corporation.

The 76-page determination of Commission chair, High Court Judge Brian Cregan, has been published online on the Government website. This determination was in response to a Department of Finance legal submission on the subject.

He has concluded that he did not have the statutory power to introduce the documents as evidence. He said the 2004 legislation setting up Commissions did not give him the power to balance the confidentiality issue against other rights, such as the public interest in disclosure. This mirrors the conclusion of a separate determination issued by the Commission in response to legal advice given to the IBRC special liquidator.

Mr Justice Cregan said that when the Commission requested documents from the Department of Finance, the Department wrote back twice during August raising a number of issues around confidentiality.

The Department said it was concerned “some of the documents might contain information which is confidential, commercially sensitive and/or privileged.

“As a result the Department was concerned that if it furnished the documentation to the Commission voluntarily it may be exposed to the risk of litigation.

“In the circumstances the Department was of the view that it would be appropriate for the Commission to issue formal directions to the Department,” to transfer the documents.

Mr Justice Cregan said “it was not simply a claim over one or two documents. It is a claim of confidentiality over thousands of pages of documents which go to the very heart of the issues which the Commission was established to investigate”.

A Department of Finance spokesman has told The Irish Times that it furnished every document that was relevant to the Commission but it had entered a "caveat" in relation confidentiality issues relating to third party documents which were in possession of the Department.

The Commission was established in July this year to investigate 37 instances where assets sales by IBRC involved a write-down of €10m or more and to find out if the decisions were commercially sound. This included the sale of Siteserv to a company connected with media and telecommunications entrepreneur Denis O'Brien, which involved a write down of €117m.

Other terms of reference included an inquiry into interest rates charged on loans to important customers and to see if there was any unusual share trade activity associated with any asset disposal.

It was due to report by the end of December but it is now generally accepted that will not occur.

The concerns raised by the Department about confidentiality are very similar to those raised by the special liquidator of IBRC.

The determination also discloses the issue was also raised by the former directors of IBRC, including the chairman Alan Dukes.

However, the directors contended that even if the documents were confidential, the Commission did have the power to overrule that in the public interest and to admit the documents.

The Commission chair said the directors were not able to point to any power in the 2004 Act setting up commissions of investigation that would allow him to do that.

Mr Justice Cregan discloses that correspondence between the Commission and the Department on this issue continued into October. In a letter sent on October 1st, the Department asserts a “duty of confidentiality” or other legal restrictions on some of the documents.

“This includes all informant relating to borrowers of IBRC and all other information received from IBRC whether provided to the Commission in the form in which it was received or whether reflected in internally generated documents.”

The Department essentially took the view that documents that originated from within the Department including memos and letters (as opposed to correspondence it received from third parties) also fell into this restricted category, if it continued information about IBRC borrowers.

The Department of Finance letter states: “The information this Department received from IBRC was received in circumstances that IBRC would have an expectation that it would be treated confidentially.

“This also includes information which the Department would have received from the Central Bank…. The Official Secrets Act 1963 also applies to official information contained in our responses.”

The Department said it had provided the information in an unredacted form with a view to facilitating the Commission’s work.

It goes on to say it is for the Commission to determine if the documents should be received in evidence. Mr Justice Cregan decided he did not have sufficient powers under the Commission of Investigation Act 2004 to make that determination. As a result the work of the Commission has ground to a half.

In his determination Mr Justice Cregan has concluded that the “duty of confidentiality does indeed apply to these documents

“This is because there is no doubt that all of these documents arise from… the banker-customer relationship.”

However, in setting out the four circumstances in which those powers are qualified, he the asks does the Commission have statutory power to perform an exercise in balancing competing rights and have an express power to vary those rights, to balance with the public right of disclosure.

“The answer to that question is , in the view of the Commission, no.”

The reason, the determination has stated, is that the Commission does not have adequate powers, in other words the power of a High Court judge which a Tribunal of Inquiry would have.