More than one in 10 of the diocese’s priests between that period were the subject of child sex abuse allegations. During the same period about one in five Marist Brothers – the order that ran Maitland and Hamilton high schools – were accused of child sexual abuse.

Between 1990 and 2010 more than 30 per cent of the John of God Brothers order, which ran a home at Morisset until 2001 for intellectually disabled boys and boys with behavioural problems, were accused of sexually abusing children.

Between 1950 and 2015 a staggering 40 per cent of the St John of God Brothers were accused of abusing children, the highest percentage of alleged abusers in any Australian Catholic order or diocese.

The royal commission heard evidence on Monday of a level of crime within the Catholic Church that is almost unprecedented for any institution in Australia, with 4444 people making reports between January, 1980 and February, 2015 alleging they were sexually abused by Catholic offenders.

The royal commission was told, and the Catholic Church accepted, that even 4444 complaints is a significant under-reporting of the true level of abuse because an unknown number of victims will never disclose. There was also evidence of church representatives deliberately not recording abuse allegations for long periods, or destroying evidence of abuse.  

The church was the subject of a disproportionate level of complaints to the commission, with 37 per cent of all people reporting abuse in a Catholic institution.

A total of 1880 alleged perpetrators were identified, and another 500 unknown people were identified as alleged offenders.

Counsel assisting the royal commission, Gail Furness, recounted details of the 15 public hearings into the Catholic Church held since 2013, including a public hearing in Newcastle in September which heard evidence of “atrocities against children”.

“In each of those hearings the experience of survivors was heard. The accounts were depressingly similar. Children were ignored or worse, punished. Allegations were not investigated. Priests and religious were moved,” Ms Furness told the commission.

“The parishes or communities to which they were moved knew nothing of their past. Documents were not kept or they were destroyed. Secrecy prevailed, as did cover ups.

“Priests and religious were not properly dealt with and outcomes were often not representative of their crimes. Many children suffered and continue as adults to suffer from their experiences in some Catholic institutions.”

In a 50-page report on Catholic abuse allegations across the country, the royal commission showed the percentage of abuser priests in Maitland-Newcastle diocese significantly increased between 1950 and 2010.

In the 1950s and 1960s about 4 per cent of priests were subsequently the subject of abuse allegations. The percentage of priests who were alleged perpetrators rose to 8.1 per cent in the 1970s, 8.9 per cent in the 1980s, and greater than 10 per cent in the 1990s and between 2000 and 2010.

At the same time other known Australian Catholic abuse hotspots such as the diocese of Ballarat experienced a drop in the percentage of abusers. While about 9 per cent of Ballarat’s priests were alleged perpetrators in the 1970s, 1980s and 1990s, the percentage had dropped to 6.7 per cent between 2000 and 2010.

Sydney parish priest and director of the church’s Aquinas Academy, Dr Michael Whelan, was pessimistic about the church’s capacity to change. Its culture was about power and “empire building”, based on a history that included the church ruling large parts of the world. It was arrogant, its denial mentality in the face of possible scandal was “abominable”, and its involvement with some of the most violent and ugly events in world history left Dr Whelan almost speechless.

“Why has the church repeatedly persecuted and oppressed Jews, tortured heretics, and why did it fight the brutal wars we know as the Crusades? I know nothing in the teaching of Jesus or the gospels that could in any way promote or justify that. I take that back to the empire model of church,” Dr Whelan said.

Ms Furness told the royal commission that requests to the Vatican for information about all Catholic child sex abusers in Australia had been declined. In 2014 it said it was “neither possible nor appropriate to provide the information requested”. The Vatican later denied a royal commission request for documents about a named Australian priest “to avoid compromising the integrity” of a church law proceeding involving the priest.

American priest and church critic Tom Doyle will give evidence on Tuesday.