Former Anglican dean of Newcastle Graeme Lawrence has been jailed for eight years for sexually abusing a 15-year-old boy in 1991.

Newcastle District Court judge Tim Gartelmann on Thursday jailed Lawrence, 77, for eight years with a minimum of four-and-a-half years after finding him guilty following a judge-alone trial of aggravated sexual assault and aggravated indecent assault.

Judge Gartelmann said Lawrence had abused his position of trust in the church to commit the offences.

“The victim and his mother must have trusted him because he was the dean,” the judge said.

“This significantly aggravates the offences.”

Judge Gartelmann said the impact of the abuse on the victim had been profound as he had been at a sensitive stage of his development when Lawrence preyed on him.

The judge believed the victim’s evidence during the trial had a “clear ring of truth” to it, while Lawrence’s evidence lacked credibility.

Lawrence, the second most senior Anglican in the Newcastle diocese at the time, preyed on the boy at his home, known as the Deanery, next to Newcastle’s Christ Church Cathedral.

The boy had been packing up equipment at the cathedral when Lawrence invited him to a group gathering at the Deanery.

The boy, who was in year 10 at the time, said there was no one else at the Deanery when Lawrence took him into a room with framed photos of naked boys on the walls.

Lawrence asked the boy if he liked the photos but the teenager said ‘No’.

Lawrence then sexually assaulted the boy.

The boy told how he was shaking and scared when he pleaded with Lawrence to stop but Lawrence kept telling him: “Just relax, it’s OK.”

Lawrence later told the boy: “Don’t bother telling anyone. You’re just a boy and I’m the dean. No one will believe you.”

The boy said he fled the room, wiped his tears away and asked his mother to take him home.

He was bleeding when he showered and felt dirty no matter how long he washed himself.

He then got into his pyjamas, cried himself to sleep, went to school the next day and never told anyone about what happened until he confided in his wife in 2016.

Lawrence denied ever meeting the boy, said he never invited him to the Deanery, and never had pictures of naked boys on the walls.

Lawrence, who became the 13th Anglican dean of Newcastle after moving from Griffith to Newcastle, was arrested after police received a referral in 2016 from the Royal Commission into Institutional Responses to Child Sexual Abuse.

Strike Force Arinya was formed to investigate allegations of sexual assault.

Lawrence, who had received an Order of Australia in 1998 for his service to the Newcastle community, was defrocked by the Anglican Church in 2012.