When David Gregory wrote to his teachers to “please help” him deal with bullies at his NSW school, he expected they would.

Instead most turned a blind eye while some even joined in the harassment, the NSW Supreme Court has been told.

Gregory, now 30, from Mollymook on the state’s south coast, suffers from obsessive compulsive disorder, agoraphobia and panic attacks and is unable to work.

He is seeking more than $2 million in lost earnings from the state of NSW, arguing the school’s failure to prevent “consistent and systematic bullying” caused his severe psychological problems.

He blames his conditions on years of humiliation and isolation he says he endured as a day student at Farrer Memorial Agricultural High School, in Tamworth, in the state’s north.

His ambitions to be a doctor, politician or work in foreign affairs were abandoned after years of bullying left him psychologically scarred, his lawyer Russell McIlwaine said.

Giving evidence before Justice Elizabeth Fullerton, Mr Gregory said a student-designed system requiring younger boys to obey senior students was in place when he studied at the school between 1991 and 1996.

If the rules were not followed, younger boys risked being “nicked” – hit across the knuckles with a steel ruler, or “broomed” – being struck with a broom as hard as possible.

“The teachers just accepted it at Farrer,” Gregory told the court.

When he criticised the system, he said, he was ostracised and name-calling and physical abuse began.

Called “sterile”, “faggot”, “midget”, “paedophile”, “Nazi” and “Aids”, Mr Gregory said he was forbidden from socialising with his peers and regularly had rocks thrown at him.

He sobbed while describing how he once disobeyed an order from an older boy and was set upon by about 20 Year 12 students.

“I felt totally powerless … I didn’t know when this was going to end,” he said.

He told the court he reported these and other events to his year master, head master, head of welfare and other teachers, and sent a letter to one teacher in which he wrote “please, I need help”, but his fears were ignored.

“I hated the place … I knew things were going to happen – they were happening to me on a daily basis,” Gregory said.

“I stopped trusting people, I stopped trusting teachers.”

Eventually, he developed obsessive compulsive disorder and also began self-mutilating, wearing extra layers of clothing to make sure “the blood didn’t seep through”, Gregory said.

When his headmaster joked during the school formal that he was “right wing in the extreme, and with his peers was often off-beam”, Gregory said it was the ultimate humiliation.

He said it felt like the teachers were involved in the bullying.

The school has acknowledged in court that it should not have allowed the students’ system to operate and that it failed to implement “adequate control so as to protect and prevent abusive conduct by the students”.

Gregory will continue giving evidence on Tuesday.