Two of the 29 charges against Malka Leifer have been dropped as the sex abuse trial of the former Melbourne school principal nears its conclusion.
Warning: This story contains details of allegations of sexual abuse.
Mrs Leifer has pleaded not guilty to sexually assaulting three sisters from the Adass Israel School two decades ago.
On Monday, Mrs Leifer was acquitted of two counts of committing an indecent act with a 16 or 17-year-old child.
The charges related to allegations Mrs Leifer touched the breast of one of the complainants, Elly Sapper, between December 1 and December 11 in 2006.
The court heard the legislation used against Mrs Leifer for those charges came into effect on December 1, 2006.
However, Judge Mark Gamble said the jury would not be able to find beyond reasonable doubt that the alleged offences occurred on or after that date.
"If that offending occurred, it likely occurred before the 1st of December, 2006," he told the jury.
Mrs Leifer will continue to be tried on the remaining 27 charges.
Mrs Leifer is accused of sexually assaulting the complainants between 2003 and 2007, while the sisters were students and graduate teachers at the Adass Israel School.
Prosecutors allege the incidents occurred in the offices of the Adass Israel School, on school camps and at Mrs Leifer's home.
Sisters' mother declined to provide a statement, court told
Sisters Dassi Erlich, Nicole Meyer and Ms Sapper took the stand for several weeks, but their evidence and cross-examination occurred in closed court.
On Monday, police informant Danielle Newton said several people contacted by police during the investigation refused to provide statements, including the complainants' mother.
During cross-examination, Detective Sergeant Newton confirmed emails and diaries Ms Erlich had provided to police three years after the allegations were raised had been lost.
Sergeant Newton also said her requests to access phone records between 2003 and 2007 had been unsuccessful.
Prosecutors have now finished calling evidence in the trial, which has entered its fifth week.
Judge Gamble said the jury would hear closing arguments from both sides from Wednesday afternoon, and could be in a position to retire and consider verdicts around the middle of next week.
