Andrew Farley during his final year at Orange High School in 2011. Credit:Central Western Daily "They are spread easily by the simple manipulation of mobile phones and computers. Their evil lies in the grapevine effect that stems from the use of this type of communication." Mr Farley, who was 20 at the time of the judgment, is the son of the school's former head of music and arts, who was described as a "gentle man who had a number of health issues". Young Mr Farley graduated from high school in 2011 and had never been taught by Ms Mickle. In November 2012, he posted a series of defamatory comments on Twitter and Facebook about Ms Mickle, who took over his father's job on an acting basis after the senior teacher left in 2008 for health reasons. "For some reason it seems that the defendant bears a grudge against the plaintiff, apparently based on a belief that she had something to do with his father leaving the school," Judge Elkaim said.

"There is absolutely no evidence to substantiate that belief." Judge Elkaim said his impression of Ms Mickle in the witness box was "of a very honest woman who had been terribly hurt both by the comments in general but perhaps more particularly by the suggestion that she may have been responsible for any harm, ill health or effect of any of her actions on the defendant's father." There was evidence that, in the absence of the comments, the senior teacher would have continued teaching as she had before "until she reached the age of 65 which is in about seven years' time". Judge Elkaim ordered Mr Farley to pay $85,000 in compensatory damages. He also ruled that the young man's conduct in response to the case warranted an additional $20,000 in aggravated damages.

Mr Farley ignored a letter from Ms Mickle's lawyers in November 2012. He removed the comments and apologised "unreservedly" only after they wrote to him again in December. Judge Elkaim said the apparent sincerity of the apology was contradicted by Mr Farley when he attempted to argue in his defence that the comments were true. He said the defence had "no substance" and was later struck out. "The defence of truth when it is spurious is particularly hurtful to a person who has been the subject of such unsubstantiated allegations," Judge Elkaim said. The judge added that Mr Farley appeared to have "abandoned his interest in the proceedings" and did not appear at the trial.

The decision is the first defamation case involving Twitter to go to trial, although earlier decisions have considered defamatory comments on Facebook. Loading Liberal pollsters Mark Textor and Lynton Crosby's Federal Court case against former federal Labor MP Mike Kelly is still at the pre-trial stage, while prominent columnist and author Marieke Hardy settled a case in 2011 for erronesouly "naming and shaming" a Melbourne man on Twitter as the author of a hate blog. Media law expert David Rolph, an associate professor at the University of Sydney Law School, said: "This case just reinforces that even private individuals are subject to defamation law on social media and should be careful about what they say."