An elderly man who was sexually abused by the Christian Brothers as a child has described the pain and fear he experienced being repeatedly raped as a nine-year-old boy at a group home for vulnerable children.

Key points: John Lawrence was repeatedly raped by Christian Brothers at two orphanages

John Lawrence was repeatedly raped by Christian Brothers at two orphanages His case is the first to come to trial since WA's statute of limitations was removed

His case is the first to come to trial since WA's statute of limitations was removed Christian Brothers lawyers dispute the amount of compensation he should receive

WARNING: This story contains material that some readers may find upsetting

Perth man John Thomas Lawrence, 75, has become the first child sex abuse survivor to testify about his ordeal in court since Western Australia removed time limits on such cases being heard.

Today, he detailed to the court the protracted abuse he suffered at the hands of Christian Brother Lawrence Murphy.

"You just can't stop crying … you're nine years old … [you've] got a big man on top of you," he said.

On Monday, the Christian Brothers admitted three brothers, including Murphy, as well as a lay teacher, Joey Jackson, abused Mr Lawrence in the 1950s.

Despite conceding the abuse, the Christian Brothers have indicated they will dispute the amount of compensation Mr Lawrence's lawyers are seeking for lost wages incurred as a result of the mental injuries the abuse caused.

Distress in court at graphic testimony

Mr Lawrence's barrister Tim Hammond spent the day questioning his client about the offences and the effect they have had on his life since.

Brother Lawrence Murphy (right) abused John Lawrence (left, sitting) while he was at the Castledare Boys' Home. ( Supplied: District Court of WA )

At the start of proceedings Mr Lawrence requested Mr Hammond be allowed to remove his black robe and appear in his suit, saying the robe reminded him of the robes Murphy wore.

Judge Mark Herron denied the request, saying the court required barristers and judges to dress in robes and taking them off was not in his view, "an appropriate way to proceed".

Under questioning Mr Lawrence then went on to describe the life he had lived since arriving in Australia as a eight-year-old migrant from Birmingham in the United Kingdom.

Mr Lawrence said he was raped by Murphy within "two or three weeks" of arriving on a ship called the New Australian.

As he described the pain of the attack, a man who identified himself as a fellow pupil fled the courtroom, visibly distressed.

"Of course it hurt, I was only a little boy," Mr Lawrence said.

"I could hear him [Murphy] breathing, he stank."

The homestead of the Castledare Boys' Home in Perth's south-eastern suburbs where John Lawrence was abused in the 1950s. ( Wikimedia: Moondyne )

It was the first of many attacks Mr Lawrence experienced during his eight years at the Clontarf and Castledare boys' homes.

Asked how the abuse made him feel, Mr Lawrence said, "inferior".

"It made me feel dirty … as if I was worthless."

Mr Lawrence went on to describe a life of alcohol dependency, overdoses, suicidal thoughts and how he met his wife inside Perth's Graylands mental health hospital.

"I've cried for 40-odd years," he said.

The trial continues.