Minister for Justice Michael McDowell only received the full contents of an internal report into Garda activities in Donegal in 2002, more than 18 months after it was completed, he told the Dáil.
As the then attorney general, the State's legal adviser, he said his office had repeatedly sought the Carty report from the Garda authorities.
He also insisted that he and then minister for justice John O'Donoghue were both anxious in 2001 to have a public inquiry.
However, he advised the minister that "to have a tribunal of inquiry could pull the plug on criminal prosecutions then pending".
In a staunch defence of his role, Mr McDowell rejected allegations by Labour TD Brendan Howlin that the Dáil had been misled, because they did not have the full contents of the Carty report.
He insisted that the "fundamental background circumstances didn't arise in a fortnight in Donegal" and that it was "a long time coming". All these events arose from a "massive systems failure" that developed under successive administrations.
During sharp exchanges he was asked to apologise and said that he would tender a formal apology to the McBrearty, McConnell and Gallagher families "on behalf of all the governments that brought about the situation in which these events occurred".
He also outlined proposals for radical Garda reforms and rejected Opposition calls for an independent police authority because the "greatest consequence would be virtually no parliamentary accountability".
Mr McDowell opened and closed a four-hour series of statements on the Morris tribunal investigating Garda activities in Donegal.
The McBrearty family observed the proceedings from the public gallery.
The Minister said that in January 2002, the appendices to the Carty report were finally delivered to him and "it was only at that point that the legal advisers advising me on the civil matters came to the conclusion that there was a very serious series of conspiracies to pervert the course of justice", and the legislation was amended to facilitate the holding of an inquiry "without pulling the rug from under the criminal prosecutions taking place".
At the time the Garda authorities failed to hand over the full content of the Carty report, there was a doctrine that because of day-to-day operational independence, the Garda - in co-operation with the DPP - could decide what to give the attorney general and the minister, a view that was "profoundly legally mistaken", said Mr McDowell.
"The whole system failed badly," he added.
The fact that gardaí "even started out on their corrupt path indicates a certain confidence on their part that they would not be challenged and stopped".
He also rejected suggestions that there was a "sweetheart" deal to allow dismissed or retiring gardaí to keep their pensions.
The Morris report stated it would be unfair to take away pension entitlements.
The Minister said he would establish a three-person ombudsman commission, one of whom would be chairman. He said the PSNI was a regional force while the Garda was the police force of the State and in England and Wales, the commission had 17 members.
He will bring significant amendments to the Garda Síochána Bill. He said:
the commission will have power to investigate any Garda practice, policy or procedure with a view to reducing the incidence of related complaints;
the commission will have power to carry out full criminal investigations including obtain search warrants, arrest gardaí and take forensic samples;
a Garda inspectorate will also be established to ensure that Garda resources are used to achieve the highest levels of efficiency and effectiveness;
the Garda Commissioner had taken steps to ensure that the culture of gardaí failing to account for the manner in which they conduct their duties was "emphatically ended".
