More than four decades after former Mildura police officer Denis Ryan was stopped from investigating allegations of child sexual abuse by a Catholic priest, Victoria Police has admitted a conspiracy to cover up the crimes went right to the top.

"It is my opinion that chief commissioner Reg Jackson was the architect of the Victoria police's response to Denis Ryan's investigations into Monsignor Day", Miller told the child abuse royal commission on Tuesday.

Mr Ryan told the inquiry he questioned the other police officer as to why they did not charge Day and was told by him: "You don't charge priests or you will be in more trouble than enough".

"The Catholics looked after the Catholics and the Masons looked after the Masons". They had taken Day and his vehicle back to the police station, where he was later picked up by two priests.

"It was like stepping stones. It wasn't hard", he told the inquiry.

When Mr Ryan asked the responsible sergeant why Day had not been charged, he responded: "You don't charge a priest or you'd be like a bastard on Father's Day, or words to that effect".

He also named Superintendent Jack Partland and Inspector Alby Irwin as being part of efforts to thwart the investigation.

Mr Ryan said he wrote to Ballarat Bishop Ronald Mulkearns about Monsignor Day, and was threatened outside Mildura Police Station by Mildura parish priest Father Peter Taffe.

Bishop Mulkearns had been called to appear before the commission, but was excused due to his poor health.

He knew most of the police members mentioned in the book, and now believed his predecessor, the late chief commissioner Reg Jackson, was the "architect" of Victoria Police's response to Mr Ryan's investigation into Monsignor Day.

"It couldn't have [happened] in the manner it did without his knowledge and consent", Mr Miller said.

"It's very satisfying, most satisfying", Mr Ryan said.

"The driving force behind his crusade was the desire to achieve justice for the victims of a hypocritical paedophile priest", Miller told the commission.

Outside court, current police Commissioner Graham Ashton said he accepted the evidence given by both men and he would be making an apology to Mr Ryan.

Mr Miller said Mr Ryan should be compensated for his treatment and "premature resignation".

"If there is compensation I would be delighted, but it certainly wasn't done for compensation".

"It's been all about saying sorry, trying to move forward and trying to make sure we don't do these things in the future", he said. Much had changed since then, he said, including the establishment of police Taskforce SANO to investigate child abuse complaints, following the Victorian parliamentary inquiry into child abuse.

"Pell became angry and yelled at me "young man, how dare you knock on this door and make demands". "He was a well-known influential priest in the area and I wanted someone of authority outside of the school to know what was happening there and somebody who would be able to do something about it".

Cardinal Pell has consistently denied that he was aware priests were sexually abusing children during his time at the Ballarat diocese between the 60s and 80s.

More damning allegations about Cardinal George Pell's intricate knowledge of the sexual abuse of boys have emerged.

Under intense cross-examination by Cardinal Pell's lawyer Sam Duggan questioned the validity of BWF's claims telling the inquiry that Cardinal Pell did not live in the presbytery in question when the alleged incident occurred.

He said he was living at St Alipius presbytery a couple of kilometres away.