The Minister for Justice will consult the Attorney General and the Garda authorities about a renewed request for an independent public inquiry into circumstances of the 1997 murders of two women in sheltered accommodation at Grangegorman.
Mr McDowell told the Independent TD for Dublin Central, Mr Tony Gregory, that he had received a letter from lawyers for the sister of Ms Sylvia Shiels - who was murdered with Ms Mary Callinan - seeking the fully independent inquiry based on the protections of the European Convention on Human rights.
"In view of the matters raised in the letter and in order to assist me in my consideration of the request, I will again consult the Garda authorities and the Office of the Attorney General. I expect to be in a position to respond to the solicitors' letter in the near future."
Mr Gregory, who raised the issue described the murders as probably the most brutal of recent times and said it would be "difficult to imagine two more vulnerable victims than these unfortunate women".
He said that if for "no other reason than the extreme callousness of the murder of these innocents, this case should be brought to finality, the person responsible prosecuted and justice seen to be done".
Ms Shiels's sister, who received not a "scrap of information directly" on the case, had this week called again for an inquiry and her solicitor identified five areas under the human rights convention, where the standards set out for investigations had not been met.
The charges against the man originally accused, Mr Dean Lyons, were dropped after Mark Nash, the man convicted of the murder of the Roscommon couple Carl and Catherine Doyle in August that year, admitted the Grangegorman murders, but then retracted his confession.
Mr Gregory asked what would have happened to Mr Lyons had Nash not confessed, and he said that if Mr Lyons "had been a person of affluence and influence and not a homeless heroin addict, it is most likely that we would have had an independent inquiry a long time ago".
The Minister said that in 1999 the Director of Public Prosecutions decided that no prosecution should take place. Mr McDowell added that he had no State function in relation to prosecution and the DPP was independent in the exercise of his functions.