MENDOZA, Argentina (AFP) — An Argentinian court has overturned the acquittal of a former nun in a notorious sex abuse case involving deaf children, authorizing a lower court to determine her punishment, according to a ruling obtained by Agence France-Presse (AFP).

Kumiko Kosaka, a Japanese national, had been acquitted in 2023 of abusing students at the Provolo Institute of Mendoza, a free boarding school for underprivileged children with hearing and speech difficulties.

The 51-year-old former nun could now face up to 50 years in prison following the reversal by the Supreme Court of Justice of Mendoza province, plaintiff's attorney Sergio Salinas told AFP of the ruling issued on Friday.

The court decision was "historic," he said.

"It means the children told the truth and the court acted very arbitrarily when it acquitted her."

A sentencing date has not yet been set.

The case, with allegations first surfacing in 2016, had sent shockwaves through the Catholic Church in the homeland of former pope Francis.

Two priests at the institute in the city of Lujan de Cuyo were jailed for more than 40 years each in 2019 for sexual abuse, including rape, of some 20 minors.

A school gardener and an altar boy were also convicted of sex crimes and sentenced to prison.

The crimes in question were committed between 2004 and 2016 and involved victims who were between the ages of four and 17.

Kosaka had been charged with aggravated sexual abuse and covering up crimes.

Eight other female employees of the school, including another nun, had faced criminal charges and all were acquitted at their 2023 trial.

The Mendoza court on Friday upheld the acquittals of the eight other women in its decision, which spanned more than 200 pages.