The Commission to Inquire into Child Abuse is to hold a public hearing on Friday to deal with the issue of the time-lapse regarding allegations.
The commission, under the chairmanship of Ms Justice Laffoy, has received between 1,500 and 2,000 statements from people alleging abuse.
The issue for this week's hearing is whether a person called to appear before the commission to face allegations of abuse is prejudiced by the lapse of time since the alleged abuse occurred.
Lawyers for those against whom allegations are being made are likely to argue that their clients' interests have been prejudiced, especially if some or all of the possible witnesses have died or become too infirm to give evidence.
Lawyers for victims will argue that the commission will be unable to fulfil its remit of getting at the truth without calling the alleged perpetrators before it.
Already there have been a number of cases in the criminal courts where alleged abusers have successfully argued that the long period which elapsed between the alleged offence and the making of the complaint made it impossible for them to have a fair trial.
The issue has been tested before the commission in relation to one individual. Last May this individual objected to being called to give evidence about an alleged incident of physical abuse in an institution in the early 1970s. It then emerged that he had already successfully challenged a prosecution by the DPP in the Circuit Court arising out of the same incident.
In the High Court, Mr Justice Kelly had ruled that the delay between the alleged offences and the complaint was inordinate, and that the case was prejudiced because a number of people who could have contributed to the defence were dead or uncontactable. The person then argued that this finding was also applicable to him being called before the Child Abuse Commission.
The commission rejected this, pointing out that the issue before the High Court concerned a criminal trial and the constitutional rights of an accused person in the criminal justice system. The commission's process is an inquisitorial one, and its function is to decide whether or not the alleged incident occurred, not to bring in a finding of guilt or innocence or impose a sentence.
The commission noted that, as a statutory inquiry, it was not constrained by issues like the presumption of innocence as in a criminal trial. It had to decide on the balance of probabilities, and would have a broader range of evidence on which to make its findings. It concluded that it was not precluded from continuing with the inquiry into the alleged incident.
As the commission's terms of reference go back to 1940, some allegations are very old, and some of those implicated may be very elderly or infirm, if not dead.
"It is the commission's view that it would not be appropriate to propound a general view in relation to these matters. Each allegations must be assessed on its merits," the commission said.
The hearing is expected to continue for a few days.