A Japanese court on Tuesday sentenced a 31-year-old former baby sitter to a prison term of 20 years over forcible sexual intercourse and other indecent acts on 20 boys aged 5 to 11 years old.

A licensed nursery school teacher, he had found some of his victims by registering on an app that connects baby sitters with families, highlighting the difficulties of keeping pedophiles away from such services.

Prosecutors had demanded that the Tokyo District Court sentence Akinori Hashimoto to 25 years in prison, while the defense argued that 10 years was proportionate.

Presiding Judge Masanori Kodama said the ruling took into consideration that Hashimoto used his position of trust to repeatedly commit the crimes over four years and four months, and that he was clearly habituated to his actions.

Kodama also cited concerns of potential effects on victims' healthy development, and the remarkably high number of children and incidents involved, to call it a particularly malicious case of its kind.

According to the ruling, Hashimoto committed the acts from 2015 to 2020 in areas including Tokyo, the nearby prefectures of Ibaraki, Shizuoka, Yamanashi and Hiroshima in western Japan. In addition to baby-sitting assignments, abuse also occurred in children's care facilities and camps.

Prosecutors said in their closing arguments that Hashimoto's "extremely contemptible" actions as a licensed nursery teacher had "hugely damaged public trust" in the profession.

The defense maintained that some of his behavior detailed in the indictment was "close physical contact" and did not constitute a crime. They also said he has a "low chance of reoffending."

In his final statement to the court ahead of sentencing, Hashimoto said he was "reflecting on the unchangeable things I have done." He also previously told the court that he would "have no connection with children in the future."

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