A former school teacher's excuses for graphic internet searches and a sexualised chat with a teen have been slammed as wholly unconvincing, as he was found guilty of a child sex offence.
William Roberto Gulson taught at Sydney's elite Knox Grammar School and conducted private tutoring before he messaged a 15-year-old girl, posing as a boy, in August 2024.
The girl and another teenager were running a fake profile on the LGBTQI dating app Grindr intending to catch pedophiles, Sydney's Downing Centre Local Court was told.
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"Do you find it hot that you're as old as some of my students?" the teacher asked after the teen said they were 15 years old and in year 9.
But Gulson testified that he never believed the user was a child and suggested a search for "gay child porn" might have been auto-filled because he had no memory of typing it.
Those denials were "wholly unconvincing", magistrate Hugh Donnelly said as he found the former educator guilty of procuring a child aged under 16 for unlawful sexual activity.
"His answers had the hallmark of recent invention," Donnelly said.
The former teacher had a sexual interest in children, the magistrate found.
That was clear in his internet searches, including "young boy raped movie scene" and "movies about priests molesting boys", he said.
After the teenager said he was 15, Gulson replied "wow you're super young" and said he was conflicted.
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"Such a cute boy," the teacher praised after receiving a photo sent by the teen.
He did not use the word adult once in the lengthy exchange, which Donnelly said flew in the face of Gulson's claims he believed he was speaking to an adult.
Instead, Gulson encouraged the purported boy to sneak out of his parents' house so they could meet up and find a "quiet place" for sexual activity, the court was told.
Gulson also described in graphic detail the sexual activity he would like to perform with the teen.
"Collectively, this is powerful evidence," Donnelly said.
Gulson, who faced a three-day hearing in September, remained impassive as the guilty verdict was handed down.
The offence carries a maximum penalty of 12 years behind bars.
His bail was continued ahead of his sentencing in March.
Gulson did not speak to reporters as he left the courthouse alongside his brother, who was at his side during the hearing.
The family of the teenager dialled into the courtroom to hear the outcome after being granted special permission.
1800 RESPECT (1800 737 732)
National Sexual Abuse and Redress Support Service 1800 211 028
Lifeline 13 11 14
Kids Helpline 1800 55 1800 (for people aged 5 to 25)
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