The Opposition strongly criticised the Government after the trial of five men accused of the murder of Kieran Keane was transferred to Dublin from Limerick.
However, a spokesman for the Minister for Justice, Mr McDowell, denied that the strategy of basing criminal trials outside Dublin had backfired.
Fine Gael's justice spokesman, Mr John Deasy, said the failure to empanel a jury in the trial indicated that the Government had failed in the basic task of protecting its citizens.
Placing the blame on the Minister for Justice, he said the events illustrated that the Government was unable to deal with the growth of organised crime.
The gang culture in Limerick had spiralled out of control, leaving citizens in fear, Mr Deasy claimed. The Government had failed to provide sufficient resources to tackle the drug problem at the root of gang culture.
Labour spokesman Mr Joe Costello said the transfer of the trial was "a serious development" for the legal and policing systems. It was a stark indicator of the extent to which people were in fear of organised crime.
"The failure to find 12 citizens willing and able to sit on a jury is a reflection of the climate of fear that has been created, largely as a result of the failure of the Government and the gardaí to take on and defeat criminal gangs," he said.
"There was probably no alternative to the decision to transfer their trial to Dublin. However, we all have to consider the implications for Irish society of a situation where it has not been possible to empanel a jury in the third-largest city in the country to hear a major trial."
The gang problem was not confined to Limerick. "There have been up to 17 gangland-type murders in the country this year so far, many of them in Dublin. There are parts of Dublin where people are living in constant fear of the crime barons."
Mr McDowell's spokesman said the Government fully supported the hearings of the Central Criminal Court in Limerick. Other cases had gone ahead in Limerick and sittings of the court in the city would continue.