It is not normal practice to carry out an inquiry when the Garda file remains open on a case, the Taoiseach told the Dáil yesterday during exchanges over the murders of two women at Grangegorman seven years ago.
Mr Ahern said he would discuss the matter with the Minister for Justice, Mr McDowell, who last week said that he was not satisfied that a public inquiry was required into the murders.
But Labour leader Mr Pat Rabbitte, who raised the issue, said there was "a fear in the public domain that a suspect was readied up for a terrible crime he did not commit".
The Dublin South-West TD said that a youth from his constituency, Mr Dean Lyons, was questioned and charged with the crime. He made a confession to the two murders, "that was expressed in the kind of detail and language that he would not have known unless it had been fed to him. Subsequently, another man admitted to what appeared to be the same crime," and the charges against Mr Lyons were dropped.
"Seven years on, is it satisfactory that no one has been charged for these crimes, and is it not a shameful way in which to treat the three families involved" - the relative of the two murdered women and of Dean Lyons -, he argued.
An internal Garda inquiry had been carried out, but the results were not made public. "Does the Taoiseach contend that because the investigation file is still open, the circumstances in which a not particularly literate youth, who was a known drug abuser, confessed in the Queen's English to circumstances about which he could not have known, must be left un-investigated?"
The inquiry would not be another public tribunal but an investigation under the Commissions of Investigation Act, into a matter of profound public interest that could be conducted speedily, efficiently and relatively cheaply, he said.
Mr Ahern acknowledged that seven years was a long time to wait. But he said that internal Garda inquiries were only published on rare occasions.
However, promising to discuss the matter with the Minister for Justice, Mr Ahern said he was sure that the Garda's view of Mr Lyons had been examined.
As nobody had been charged with the murder he understood the investigation remained open, in which case an internal investigation would not be undertaken.