Mr Andrew Madden, the first man in the State to go public on his abuse as a child by a priest, has described Ireland as "a better place than it has been" to speak or act about abusive experiences.
While critical of the Taoiseach, Mr Ahern, for his handling of the issue, Mr Madden has praised the Minister for Justice, Mr McDowell, and the Minister for Health, Mr Martin, for their"speedy and decisive" responses.
In an address to be delivered today to students at Coláiste Dhúlaigh in Dublin, he will say his action against Dublin priest Father Ivan Payne and the Catholic Church was initiated in 1991.
By 1993 "with some help from Archbishop Desmond Connell as he was then, I had received what I consider to be nominal compensation (almost £30,000).
The amount of money was small but as an event it seemed huge.
I felt that a very important precedent had been set and I was determined that one day everyone should know about that settlement and others should have their opportunity to seek compensation if they so desired," he said.
In 1995 he revealed details in an Irish Press interview, without giving either his own or Father Payne's names.
"No one had spoken out publicly about sexual abuse at the hands of a Catholic priest in this country at that time and certainly no one had spoken about having been compensated," he said.
But he wanted to correct pronouncements by the church that it would never compensate people who had been sexually abused by priests.
"And I also wanted to put into the public domain the provable fact that a priest with a known record of child sexual abuse was still a serving priest in a Dublin diocese," he said.
In June 1998 the Taoiseach, Mr Ahern, turned down his request for a public inquiry into clerical child sex abuse as the church was not a public body.
It was also feared such an inquiry might be challenged as unfair, legally, if it focused only on the church and its scale would be "so great" it was difficult to see how it could be effective.
Such inquiries also were "for the purpose of inquiring into definite matters of urgent public importance," the Taoiseach said.
"In my opinion Mr Ahern was guilty of engaging in the most shallow populism by seeking not to offend the Catholic Church," Mr Madden said.
He added he was "very disappointed with the Taoiseach and I repeat I considered it an act of considerable cowardice on his part not to act at that time".
He doesn't believe the church has changed "in any way at all" where the issue is concerned.
"Its primary concern has always been the protection of the institution of the church, its resources and its power."