In public, the Catholic Church has made promises of compassion to survivors of child sexual assault for decades.

Privately, however, it empowered lawyers to "strenuously" defend every Common Law claim brought against the institution.

"The way the church is treating us now is actually adding to the abuse we suffered when we were kids," a survivor confided.

The church has built a ruthless reputation for its range of legal tactics, from stonewalling to counter-attack.

One of the worst known examples of intimidation occurred in the 1990s, when a long-suffering survivor sued the church for allowing a paedophile priest to work in several parishes, leading to horrendous crimes.

The church denied the victim's allegations (even though it knew the priest had abused children for about 40 years) and made an outrageous threat.

Without mercy, the church stated that if the paedophile cleric was "negligent" the boy was "guilty of contributory negligence" for:

failing to take care for his own safety

failing to take care for his own safety failing to make any complaint in relation to the alleged conduct

failing to make any complaint in relation to the alleged conduct failing to seek assistance

failing to seek assistance failing to report any such alleged conduct

The intimidation worked — it usually did — and the survivor eventually abandoned his litigation.

Another defence mastered by the church over many years has been its argument the hierarchy should not be held responsible for the actions of priests.

Some in the church maintain their global organisation, whose managers go by "His Holiness" or "His Eminence", has a "flat structure".

This issue was first discussed on television in the 1996 Four Corners episode Twice Betrayed, featuring an interview with Melbourne's former church administrator Monsignor Gerald Cudmore.

Not even this vicar-general believed the flat church theory.

The interview, for context, began:

Journalist Sally Neighbour: How much concern is there within the church over legal and financial liability? Monsignor Cudmore: Obviously there is some. I believe as custodians of the church's material goods, like any housekeeper, one must be conscious of that. Neighbour: Protecting the assets? Monsignor Cudmore: Protecting the assets, that's right.

Monsignor Cudmore struggled for reasoning when asked by Neighbour whether he agreed with his boss, Archbishop Sir Frank Little, who said bishops were not in charge of lower-ranked clergy.

Monsignor Cudmore: Um, I'm not sure I understand what he said and why he said that. I can't explain that. Neighbour: It doesn't make sense to you? Monsignor Cudmore: No, no. Neighbour: And it's not a tenable argument as you see it? Monsignor Cudmore: I don't think so. And I think that's been misunderstood because clearly a priest of the Archdiocese of Melbourne is under the jurisdiction of the Archbishop of Melbourne.

It has since been revealed Sir Frank did not report paedophile priests to police and therefore contributed to the cover-up of serious crimes.

In 2014, the church conceded under oath at the Royal Commission into Institutional Responses to Child Sexual Abuse some of its legal tactics were unfair "from a Christian point of view".

Why would bishops and archbishops use unchristian tactics?

Because they have saved the Australian arm of the Roman Catholic Church its cities of riches.

Last month, Four Corners aired another episode delving into clergy sex abuse.

Set in Philadelphia, Dark Secret told the story of "one of the worst criminal cover-ups in American history".

A district attorney unearthed "secret files" — 45,000 documents — proving the deliberate obstruction of justice by high ranking clergy.

It all rang true because the same thing has happened here.

Our biggest royal commission has unearthed 1.2 million documents from many religious and non-religious institutions, despite the Vatican's refusal to release all its secret files.

Enough evidence, including confidential letters between lawyers, insurance officials, cardinals, bishops and priests, has been produced to know the anatomy of Australia's largest criminal cover-up and who was responsible.

New Common Law claims based on these discoveries are being made against the church.

Many more will follow.

Church leaders all over the country will have yet another opportunity to do the right thing.

Ballarat Bishop Paul Bird's gesture to be listed in legal cases so claimants can identify a defendant is almost meaningless if his lawyers continue to pursue the same old defences.

And if the church thinks its opposition to survivors seeking justice is fair enough, it should at least stop making public statements that it cares more for damaged children than its own wealth.