The Catholic Church in Wollongong is facing fresh allegations that it failed to follow up sex abuse crimes by its priests.
Former Catholic school principal Jim Walsh intends to tell the Royal Commission into Institutional Responses to Child Sexual Abuse that he suspects two former priests from the Illawarra, who were never investigated by police or charged.
''It is my belief that there are still some who haven't been unearthed,'' he said.
His testimony will raise the possibility the Church protected priests by moving them away from their parishes to avoid investigation.
In one case, he believes a priest was moved to avoid scrutiny.
''I thought that was strange because both of these men had creature comforts," Mr Walsh said.
"Now I know what it was, it was waiting for the heat to die down of the allegations against them.''
Mr Walsh is calling for fresh investigations to determine why the Church acted as it did.
He worked as principal of a number of Catholic primary schools in the Illawarra during the 1980s and 1990s and was vocal in his support for two victims of former priest Father Peter Lewis Comensoli.
The Wollongong priest was jailed for two years in 1994 after pleading guilty to the indecent assault of altar boys.
The court case followed a campaign by Father Morrie Crocker to expose paedophile priests in the region.
Mr Walsh became friends with Fr Crocker, who committed suicide at his boxing gym in 1998, and has written a short biography of the Berkeley priest.
He believes his career with the Catholic Education Office came to an abrupt end after he publicly supported Fr Crocker's support of abuse victims.
The ABC contacted the Catholic Diocesan Office in Wollongong but received no comment.