An ex-teacher has had her historical sex abuse charges quashed because the relevant 1970s laws did not apply to women abusing boys.
Helga Lam, a former teacher at a Sydney boys' school, had been charged with 15 counts of indecent assault on four school boys for alleged offences dating back to 1978.
But the top criminal appeal court in NSW tossed the charges on Monday, with three judges agreeing to quash the indictment.
In his lead judgment, Justice Anthony Meagher said the decision was made solely on the basis that the law in force at the time - repealed and replaced in 1984 - did not apply to "conduct committed by a female upon a male".
The relevant law was "directed to the crime of sodomy upon a male and other male homosexual conduct", he said.
"The only sexual conduct capable of constituting an assault upon a male which of its nature alone was necessarily regarded as 'indecent' at the time ... was male homosexual conduct," Justice Meagher said.
Claims against Lam included penile-vaginal intercourse with the complainants, as well as masturbating them, performing fellatio on them and telling them to perform sex acts on her.
Three complainants were willing participants, while the fourth said "he was fearful and upset when the applicant performed sexual acts upon him", Justice Meagher noted.
At the time of the alleged offending, the students were aged between 13 and 16.
Lam's case is listed to return to the NSW District Court in mid-March.
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