The Tanaiste, Ms Harney, has said the State has no obligation to pay compensation to people who were abuse victims as children "in ordinary schools".
In a letter to representatives of victims of a midlands teacher, Donal Dunne, she distinguished between those who suffered abuse in institutions and those who did so in schools.
Dunne, of Portarlington, Co Laois, was sentenced to two years in February 1999 for sex offences going back many years in midlands schools.
Ms Harney said: "The State, through these public bodies [institutions], to a significant degree replaced parents as the natural protector and care-giver of the children concerned."
This conferred on the State a special legal and moral responsibility for the welfare of those children, she said. But "a similar responsibility did not apply in the case of children who continued to live in their homes and community."
Once a person can establish that he or she suffered abuse in an institution in which he or she was resident then, regardless of issues of liability in law, it can be argued that the public authorities failed in their responsibility, she said.
"In the case of ordinary schools, public authorities did not have the level of responsibility and had no authority to exercise it.
"In the circumstances, the distinction now being made in the provision of financial redress, and in that matter only, between abuse victims in ordinary schools and victims in residential care institutions is a reasonable one," she said.
A spokesman for the Donal Dunne victims' group, reacting angrily to the letter, said the Tanaiste was wrong to suggest that the issue of abuse in day schools was of secondary importance to that of institutional abuse.
In deciding that the State had no authority to act where abuse in primary and secondary schools was concerned Ms Harney had pre-empted the findings of the Laffoy Commission, he said, and had exonerated those officials who had decided to do nothing about the Dunne case, despite being notified about it as far back as 1982.
He also said Ms Harney's comments were totally at variance with the assertion of the former education minister, Mr Martin, in the Dail on December 3rd, 1998, that the way in which the Department had dealt with the case was "seriously lacking even by the standards of the time".
The spokesman pointed out that the State possessed powers to remove a teacher for serious misconduct, a power not exercised in the Dunne case, and that relevant school patrons and management derived their authority from the State.
"The attitude of persons in authority, that they had no responsibility to act and no authority to intervene, left countless children at risk and enabled abusers like Donal Dunne to continue their abuse. Those persons will find solace in the views of the Tanaiste as expressed in her letter," he said.
The spokesman said the group was "extremely disappointed" with the Opposition parties on the issue and accused them of following the Government line.
He called for the setting up of a tribunal to address the matter.
Meanwhile, the Survivors of Child Abuse (SOCA) group is to hold a meeting in Liberty Hall, Dublin, on Saturday at which it is proposed "to return the Taoiseach's apology of May 1999 on the grounds that it is insincere and totally meaningless in the light of recent developments on issues of great importance to those who suffered abuse in their childhood."
Mr Ahern had expressed regret on behalf of Irish society for failure to act in the past on child abuse.
