The Catholic Archdiocese of Melbourne announced "with sorrow" the death of the former Bishop of Ballarat, Ronald Mulkearns.
Mr Mulkearns had been accused by Cardinal George Pell of deceiving him about the actions of priest, Gerald Risdale, a paedophile who committed more than 130 offences against young boys in Ballarat, Victoria state, between the 1960s and 1980s.
Cardinal Pell (pictured above) gave evidence last month via video-link from Rome to an Australian Royal Commission into sex abuse.
Bishop Paul Bird from the Catholic diocese of Ballarat said: "Those who knew [Ronald Mulkearns] personally will remember a man who was dedicated in his service over those years and, indeed, over the sixty years he served as a priest.
"At the same time, Bishop Mulkearns himself acknowledged that he had made some tragic mistakes during his time as bishop.
"He expressed his sorrow for these mistakes in the evidence he gave to the Royal Commission in February.
"The Royal Commission had foreshadowed a further hearing of evidence from Bishop Mulkearns.
"His death means that the Royal Commission and survivors will not be able to hear any further evidence that he might have given and this will be a disappointment to them."