A member of Pope Francis' handpicked commission to end child sexual abuse in the Catholic Church has called on a top Vatican official to step down amid allegations he failed to protect children when he was a senior church official in Australia.

Peter Saunders, who sits on the Vatican's Child Protection Commission, told Australia's 60 Minutes on Sundaythat Vatican finance chief Cardinal George Pell should resign because he "has a catalogue of denigrating people, of acting with callousness, cold-heartedness, almost sociopathic, I would go as far as to say, this lack of care."

"I think it's critical that he is moved aside, that he is sent back to Australia, and that the Pope takes the strongest action against him," Saunders said.

Saunders, a British survivor of child abuse perpetrated by priests, was appointed to the Catholic Church's child protection commission by the pope six months ago. Pope Francis appointed Cardinal Pell to be his chief of finance in February.

Pell, who denies all allegations made against him, issued a statement on Monday saying he had sought legal advice over Saunder's comments. "Cardinal Pell has never met Mr Saunders, who seems to have formed his strong opinions without ever having spoken to His Eminence," said the statement.

Saunder's criticism is linked to a series of allegations that have emerged in recent weeks in Australia. The most serious is from David Ridsdale, a survivor of abuse at the hands of a priest, who said in sworn testimony that when he told Pell about the abuse he'd suffered, Pell responded: "I want to know what it will take to keep you quiet."

The evidence was heard on May 20 by Australia's Royal Commission into Institutional Child Sexual Abuse, an inquiry with vast legal powers that was established in the wake of allegations that Catholic church officials sexually abused children with impunity for years, and then worked to cover up the crimes. The commission has heard that the southeastern Australian town of Ballarat was the site unprecedented levels of abuse, with up to 14 priests accused of abusing as many as 130 victims.

Pell is from Ballarat, and he spent many of his formative years as a priest there. He has had several accusations levelled at him during the inquiry of helping to cover up child sexual abuse, which he has strenuously denied through press releases issued from Rome.

The main allegations revolve around David Ridsdale, who as a child was sexually assaulted by Gerald Ridsdale, his own uncle and a notorious paedophile priest. Gerald Ridsdale has since been convicted of over 140 charges relating to 54 victims and is currently serving an eight year prison sentence, the latest of three stints he has spent in jail for sexual assault charges.

David Ridsdale recounted the moment in 1993 when he called Pell to tell him about the abuse.

"His first reaction was, 'Oh, right'. There was no shock," Ridsdale told the inquiry. "His tone then became terse relatively quickly and I could sense anger in his voice. I started to get a sense he was insinuating things about my story and I felt like I'd done something wrong."

David Ridsdale said Pell asked him what it would take to keep Ridsdale quiet.

"My response was, 'Fuck you George [Pell], and everything you stand for.' I hung up the phone," David Ridsdale told the inquiry.

Gerald Ridsdale had lived in the same presbytery residence as Pell when both men were young priests between 1972-1973. During his testimony at the inquiry, Gerald Ridsdale admitted to raping a young girl in the residence during his time there. He told the inquiry he did not remember "having any dealings with George [Pell] at all" despite them being two of only three people living in the building.

Senior Catholic officials in Australia moved Gerald Riddle around the country as he continued to sexually assault children. The committee with responsibility to move priests is known as the Consultors Committee. By 1982, when Ridsdale was moved out of the town of Mortlake, Pell was a member of the committee, and a central question of the inquiry has become whether Pell knew Ridsdale was being moved out of Mortlake because he had abused children there.

"His tone then became terse relatively quickly and I could sense anger in his voice. I started to get a sense he was insinuating things about my story and I felt like I'd done something wrong."

Ridsdale had abused several boys in Mortlake and families had complained to the church. Ridsdale told the inquiry there"was no secret around Mortlake eventually about me and my behaviour."

The Consultors Committee met under the leadership of Bishop Ronald Mulkearns who had ultimate authority on the decision, and decided to move Ridsdale.

The minutes of that meeting read: "The Bishop advised that it had become necessary for Father Gerald Ridsdale to move from the parish of Mortlake. Negotiations were underway to have him work with the Catholic Inquiry Centre in Sydney. A new appointment to Mortlake will be necessary to take effect after October 17."

Conditions of his employment in Sydney were that he underwent counselling and was barred from working with children. The church never informed police about any suspicions or evidence they may have had about Ridsdale's abuse.

Several witnesses have testified that Mulkearns was aware of complaints against Ridsdale, but it has so far been impossible to determine whether the rest of the committee had any idea. Pell has previously said Mulkearns stymied the church's ability to act on abuse, testifying that he understood Mulkearns had destroyed church documents relating to paedophilia cases.

The law finally caught up with Ridsdale in 1993 when he faced his first trial for child abuse, thanks in part to testimony from his nephew David. Pell accompanied Gerald Ridsdale to court on the first day of proceedings. Ridsdale testified last week that he had no memory of why Pell was there and said his barrister had organized Pell's appearance.

The very next day Ridsdale recanted that, conceding that he and not his barrister had asked Pell to attend the court with him. "It looks like I must've done that, yes," Ridsdale said. Pell denies knowing anything about the abuse.

"I have been accused of being complicit in the moving of a known paedophile, of ignoring a victim's complaint, and of bribery," Pell said in a press statement in late May, one day after David Ridsdale testified to the commission. "These matters again require an immediate response and it is important to correct the record particularly given the false and misleading headlines."

Sexual abuse victims' groups criticized Pell's response.

"It is vastly inappropriate to respond to sworn evidence by courageous survivors with a media statement that callously dismisses their experience," the head of the Survivors Network of Those Abused by Priests, Nick Davis, said in a statement.

The allegations will almost certainly be probed further at the inquiry. Lawyers acting on behalf of the Catholic church have generally waived their right to cross-examine witnesses at the inquiry out of sensitivity to victims, but have informed the royal commission that it may have to recall witnesses for cross-examination after the allegations against Pell and his strenuous denials.

If Pell were to be fired or resign it would represent the biggest scalp yet in the global child abuse scandal. He is the first-ever head of Vatican finance and has a mandate from Pope Francis to clean up the Church's unwieldy financial structure.

Vatican finance has previously been kept in a state of opaque, impenetrable complexity. The situation led to the Vatican bank scandal of 2013, when authorities alleged Vatican officials were involved in a plot to smuggle 20 million euros out of Switzerland and had laundered millions for businessmen from Naples.

Such were the financial irregularities at the Vatican that in February Pell announced he had found $1.5 billion in assets the Church did not even know it possessed.

He is also believed to be the spiritual advisor to Australia's Prime Minister, Tony Abbott, who himself once studied to become a catholic priest.

Pell has weathered similar storms before. He appeared before the same child abuse inquiry twice last year, showing contrition that during his time as head of the Sydney Archdiocese he spent $1.5 million Australian dollars on lawyers defending a church official against child abuse charges where a victim had only sought $100,000 and an apology from the church.

Follow Scott Mitchell on Twitter: @s_mitchell

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