A former school teacher who sexually abused his student is now pursuing his victim for almost $20,000 in legal costs.

The teacher, who was employed at the Blue Mountains Grammar School in the early 1970s, was convicted for molesting his former student, but he now wants him to pay his legal bill.

Mark Wurth was repeatedly abused at the school by the then-house master and geography teacher, Neville Gilbert Betteridge.

"He was coming into the dormitory through the infirmary of a night and taking me from my bed back to his room," Mr Wurth told the ABC.

"He was a very big drinker. Cigarettes and alcohol were involved every single time."

In 2004, Betteridge was convicted of two counts of indecent assault on Mr Wurth and was given a three-year suspended jail term.

Seven years later, Mr Wurth decided to sue the Anglican Church Diocese, which ran the school at the time, and Betteridge for damages.

The church paid Mr Wurth an out-of-court settlement and Mr Wurth then offered to withdraw the action against Betteridge.

He was shocked to receive a letter from Betteridge's lawyers demanding that he pay the former school teacher's legal costs.

"I was just [saying] 'You're joking, you know, like when does a victim pay a perpetrator's costs?'" Mr Wurth said.

"Then it got into the legalities of the whole thing and I just found it traumatising again, that he's demanding I do that.

Sex abuse victim Mark Wurth says he feels traumatised by the legal process.

"It feels very similar to how I felt when he was abusing me as a kid.

"I got no control. I'm just made to do what he says, in effect. There's nothing I can do.

"The settlement I got from the Anglican Church is just getting eaten away. It seems like the settlement was just here to feed the legal profession."

Betteridge declined to comment, but his barrister Paul Glisson said his client was entitled to seek costs under part 42, rule 19 of the Uniform Civil Procedure Rules 2005.

"Mr Betteridge has a right to get his costs under the rule, unless the court orders otherwise," Mr Glisson said.

"Mr Wurth has been compensated by the Victim's Compensation Tribunal and by the Church and he has decided to bring an action against a 70-year-old pensioner with no assets."

The Anglican Church is calling on Betteridge to drop his claim against Mr Wurth, describing his predicament as "absurd".

"We would like to express our total abhorrence of sexual misconduct or any form of abuse involving children. In this case, the pain and distress of these incidents are obvious long after the events took place," a spokesman said in a statement to the ABC.

"We hope that the settlement we have reached on Mr Wurth's claim may provide a measure of closure for him.

"However, it seems absurd there is now an action by the perpetrator to recover costs from the victim in relation to the separate claim made against him.

"We would urge that this action be dropped and Mr Wurth be spared further anguish in court proceedings."

Anglican Church using Ellis defence, says MP

NSW Greens MP David Shoebridge has been supporting Mr Wurth through his legal case.

Mr Shoebridge said before settling, the Anglican Church had relied on the so-called "Ellis defence", arguing it was not a legal entity which could be sued.

"I am pretty sure most people would have thought some of these legal defences are being limited to the Catholic Church," Mr Shoebridge said.

"What we have seen here, astoundingly, is the Anglican Church using the exact same legal shenanigans, legal ruse, to avoid paying fair compensation. They are saying that the school doesn't exist in law."

He was also alarmed that the Church said it did not have insurance to cover Mr Wurth's claim.

"It is surprising the State Government hasn't recognised the extent of the problem and be demanding all private schools, all Catholic schools, all independent schools as a basic element to their registration have adequate insurance or adequate assets to meet these claims," Mr Shoebridge said.

"Because without that comfort it is difficult to see how anyone can rest assured when they leave their kids over the school day."

Push for law reform for child sexual abuse victims

Senior Sydney barrister, Dr Andrew Morrison SC, is also pushing for law reform to protect victims of child sexual abuse.

Dr Morrison is head of the Australian Lawyers Alliance, which has made a submission to the royal commission on child sexual abuse titled Obstacles in the Way of Bringing Common Law Claims.

"There must be a legal entity capable of being sued, in respect of all organisations, of substantial size, which care for children," Dr Morrison said.

"There must be in respect of organisations such as the Catholic Church, which has avoided its liability through the Ellis defence in the past, a period when the limitation problem is lifted to allow former claimants to sue.

"The legal entity which is created must exist retrospectively so that unlike the offer that Cardinal [George] Pell made at the royal commission that would create an entity for the future, the thousands of victims who have come forward to the royal commission will have a remedy."

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