Political uncertainty over dealing with Northern Ireland's troubled past needs to be addressed, the Director of Public Prosecutions (DPP) has said.
With more than 3,500 deaths and countless more injured during the conflict, politicians should decide whether to attempt to prosecute historic cases or to forego investigations to "embed" the peace process, Barra McGrory QC added.
He highlighted difficulties including impaired memories, dead witnesses or perpetrators and limitations using modern evidence-gathering methods like DNA and said his Public Prosecution Service (PPS) would need to be properly resourced for any large scale investigation.
But he said he would continue to prosecute where the evidence existed to deliver true justice.
"Perhaps the time has come when our society should reflect on how we are going to address these issues because we appear to be drifting along at the moment in a sort of vacuum of some uncertainty," he told a transitional justice conference in Belfast.
"As the Director of Public Prosecutions I don't think it is my role to deny any victim of an injustice the delivery of true justice to that person or his or her family. As the DPP that is what I must strive to do in the current circumstances."
Sinn Fein has called for a truth and reconciliation commission to consider the fall out from Northern Ireland's 30 years of violence and wants the state to participate after its forces were responsible for some deaths. Senior MLA Mitchel McLaughlin recently proposed separating truth from reconciliation until that is done. Democratic Unionists believe victims should not be denied the right to justice.
Mr McGrory said if the prosecution service was going to be expected to deliver prosecutions then it needs to be properly resourced.
"I think society has got to make a choice. Either it decides now to go down the route, the very difficult route, of determining that we are going to forego the investigation and prosecution of the past in favour of embedding the political institutions or the peace process, or between that and deciding whether or not the peace process is best served by continuing to prosecute the past," he added.
"If it is going to be the latter then I think there needs to be a very clear investigative structure established with very clear lines of definition and with significant resources and if that is going to be done it needs to have terms of reference which will cover all criminality from all sides. The prosecutorial aspect of this will have to be significantly resourced as well. That has not yet happened."