David Maurice Withyman, 23, served almost a year in jail after he was convicted for carrying a loaded firearm with the intent to commit an offence, following a series of assaults.

But he claims the genesis of his crime spree lay in the termination of his 2003 relationship with the woman he loved, Anna Lucinda Blackburn, who at 28 was the youngest teacher on staff at Carenne Public School, a special school in Bathurst where he had been sent because of behavioural problems.

Judge Ray McLoughlin ruled in the District Court last week there was prima facie evidence the school and teacher had breached their duty of care to Mr Withyman and he should be allowed to put his case to a judge.

Ms Blackburn, meanwhile, will appear in the NSW Industrial Relations Commission today with an unfair dismissal claim against the NSW Department of Education.

In a real life version of the Cate Blanchett movie Notes On A Scandal , the court heard that Mr Withyman believed he was "God's gift to women" when at age 17 he started spending time alone with Ms Blackburn in her classroom.

They developed a relationship that became sexual after she separated from her husband and moved into her own place. She introduced him to her family and took him to Wagga Wagga for her cousin's 30th birthday.

He told a psychologist, Anna Robilliard, he thought it was "cool rooting a teacher" and described Ms Blackburn as "loving" and "gentle", in a report tendered in court. But after an intense eight- month relationship, Ms Blackburn ended the affair in October 2003 and Mr Withyman allegedly became suicidal. He attacked her five days later and was charged with assault occasioning actual bodily harm.

She obtained an apprehended violence order, but he breached it and assaulted her several other times, culminating in his firearm offence in October last year.

Mr Withyman, the son of a senior officer at Kirkconnell Correctional Centre, told Dr Robilliard as recently as January he could not get over the break-up. "I've tried but I can't move on, I won't let myself," he said.

He said he intended to kill Ms Blackburn, her current partner, her baby and himself.

Mr Withyman will sue Ms Blackburn and the state of NSW, claiming he suffers from depression, post-traumatic stress, drug dependence and suicidal and homicidal thoughts, and was ultimately incarcerated as a result of the relationship.

He claims the school was aware an inappropriate level of intimacy was developing between Ms Blackburn and himself, and knew he had borderline intelligence and attention deficit hyperactivity disorder.

The court heard this was demonstrated on a school excursion to a swimming pool, when Ms Blackburn wore a bikini while supervising the young men, including Mr Withyman, who threw her into the water in front of other teachers.

The principal also warned Ms Blackburn against her private classroom meetings with Mr Withyman.

Judge McLoughlin said on Wednesday that Mr Withyman's criminal behaviour "prima facie may well be caused by [the effect of] the relationship breakdown on the plaintiff's psyche".

"Student and teacher should never have entered into such a relationship," he said.

Ms Blackburn told the Herald yesterday that only Mr Withyman's version of events had been heard in court, but she did not want to comment until she had her day in the witness box. "It's been a fairly harrowing experience for all of us," she said. "I've got two kids in school and I'm trying to keep it private."