Cardinal George Pell, the most senior Catholic cleric ever charged with child sex abuse has been convicted of molesting two choirboys moments after celebrating Mass, dealing a new blow to the Catholic hierarchy's credibility after a year of global revelations of abuse and cover-up. Picture: Andy Brownbill/AP

Canberra - Australia's Cardinal George Pell has become the highest-ranking Catholic to be convicted of child sexual abuse after a Melbourne court found him guilty of raping a choirboy and molesting another in the 1990s.

Pell was the prefect of the Secretariat for the Economy in the Vatican, making him effectively the third most senior figure in the church hierarchy, until he received an indefinite leave of absence from Pope Francis to face the charges in Australia in 2017.

A jury at the County Court of Victoria unanimously found Pell guilty on December 11 after more than two days of deliberations, but the conviction was only made public on Tuesday after a suppression order was lifted.

Pell maintained his innocence throughout the trial, which came after a jury at an earlier trial failed to reach a verdict.

The 77-year-old, who faces a potential maximum 50-year prison term, remains on bail with his pre-sentencing hearing set to begin on Wednesday. He will likely be sentenced in mid-March. His lawyers have filed an appeal. 

As he left the court on Tuesday Pell was swarmed by media and heckled by bystanders. He made no comment. 

The jury, made up of eight men and four women, found Pell guilty on all five charges, including one charge of sexual penetration of a child under the age of 16 and four charges of indecent assault with a child under the age of 16.

Pell had just become archbishop of Melbourne when the alleged incidents took place in St Patrick's Cathedral. 

His victims were two 13-year-old boys on scholarships at the city's prestigious St Kevin's College.

The pair had left the choir group after a Sunday mass in late 1996 and were caught drinking sacramental wine in the priest's sacristy.

Pell then exposed his penis from beneath his ceremonial robes and molested them, the court heard. 

"I was young and I didn't really know what had happened to me. I didn't really know what it was, if it was normal," one victim told the court. Now in his mid-30s, he brought the allegations to police in 2015.

The other victim died in 2014.

The jury heard about four weeks of evidence from the complainant and several witnesses. Pell did not give evidence, but a 2016 video of an interview with Australian police he gave when he was in the Vatican was broadcast to the court.

Chief Judge Peter Kidd had asked the jury not to make Pell a "scapegoat" for all the failings of the Catholic Church.

A 2017 Australian inquiry found 7 per cent of the country's priests had allegedly sexually abused children between 1960 and 2015 and 62 per cent of victims who reported abuse in a religious institution were from Catholic-managed institutions. 

The guilty verdict was made public only after prosecutors decided not to go ahead with a second trial over allegations that Pell had indecently assaulted boys at a swimming pool in his home town of Ballarat in the 1970s. 

The decision was largely due to lack of evidence. One of Pell's key accusers in the case also died in January 2018. 

The court suppression order was to prevent the second trial from being influenced by the verdict of the first trial.

The victim in the cathedral trial sent an email statement to media organizations on Tuesday, asking for his identity not to be revealed and saying, "it has taken me years to understand the impact on my life."

"Like many survivors, I have experienced shame, loneliness, depression and struggle," he said. 

"The process has been stressful and it is not over yet. I need space and time to cope with the ongoing criminal process," the victim said. 

Pell's lawyer, Paul Galbally, said the cardinal had always maintained his innocence and continued to do so.

"An appeal has been lodged and he will await the outcome. In the meantime, the cardinal doesn't have anything further that he wishes to say," he told reporters outside the court.

Galbally also said the all of the complaints and allegations have been withdrawn or discontinued, except "for the matters that are subject to the appeal," which related to the cathedral trial. 

Pell had initially faced more than 20 charges of sexual abuse involving various complainants.

In recent years, the Catholic Church has struggled to deal with a slew of damaging allegations relating to sexual abuse and alleged cover-ups by priests around the world.

Last week, the Pope addressed the scandal by hosting a four-day summit on the issue, calling for an "all-out battle" against such crimes.