John Vincent Roberts was a teacher at the prestigious single-sex school when he allegedly repeatedly molested and raped the 12-year-old boy while on school grounds.

Police charge sheets presented in court claim Roberts’ carried out several acts of indecency upon the child, including fondling his penis and anus, and masturbating him.

Roberts is also accused of rubbing his own erect penis over the boy’s body at least twice in an 18 month period.

Police allege Roberts’ sexual attention towards the boy escalated into rape on several occasions.

The alleged incidents were not reported to police at the time, however officers became aware of the accusations after they were aired last year during the Royal Commission hearings into institutional child sexual abuse.

Roberts, now aged 73 and living in Fairlight on Sydney’s northern beaches, was arrested after voluntarily attending Redfern Police Station on December 14 at the request of investigating officers.

He was charged with 21 offences in total, including multiple counts of homosexual intercourse (teacher of pupil) and indecent assault where the victim was under his authority.

Roberts was released on conditional bail at the time.

In Wollongong Local Court on Wednesday, Roberts’ lawyers said they had received the majority of the brief of evidence against their client and were in a position to consider their next move.

The case was adjourned to April 20 for further mention.

Roberts was allowed to remain on bail.