TOKYO (TR) – A former teacher is on trial here for using hidden cameras to secretly film girls at his school.
Atsuto Sato stands accused of filming sexually explicit images and providing sexually explicit images. He admitted to having carried out tosatsu (secret) filming dozens of times prior to his arrest last year.
During the hearings, the full scope of Sato’s crimes have been revealed, including his assertion that once he started he just could not stop, reports the site for weekly tabloid Friday (Mar. 10).
“Get some good shots”
On November 12, 2025, Katsushika Police Station arrested Sato, 33, then a full-time lecturer at a private girls’ middle school, for providing five images of girls’ skirts taken at the school where he worked. He shot the pictures on three separate occasions between June 29 and July 5.
In July, police arrested another man for secretly filming women at a train station. Analysis of the man’s smartphone revealed that Sato had provided the secretly filmed images.
Sato admitted to the charges and was subsequently dismissed from his job at the girls’ school.
“I thought that girls were less wary inside the school than when they were walking outside, so I could get some good shots,” Sato told the Tokyo District Court on February 25.
“For the thrill”
The prosecution stated that Sato started secretly filming around spring 2023. That November, he was caught secretly filming a high school girl’s underwear at a train station, which led to counseling.
However, by summer 2024, he began using a pen-type camera he had purchased for this purpose to film the underwear under the skirts of students at the girls’ school where he worked.
Sato stated, “Students wouldn’t be as wary of being filmed inside the school, and it would be easier to film them there than at the train station.” He said he committed over 100 acts of secret filming before his arrest.
Regarding his reasons for starting, the defendant stated that he had met “like-minded individuals” on an online bulletin board. He said, “I saw those kinds of videos on the internet and thought I could do it myself. And when I was stressed, I started secretly filming.”
However, as he continued to engage in this form of voyeurism, his motives seem to have changed.
“The initial reason I started was, of course, to satisfy my sexual desires,” he said. “However, at some point, the act of secretly filming itself became the goal, or rather, I started doing it for the thrill.”
“Cobalt” and “Hunter A”
Sato also spoke of his relationship with the man whose smartphone contained images sent by him.
Sato said, “I met this man on an online bulletin board. He called himself ‘Cobalt.’ He was a man who liked to secretly film students at the school where I worked. As we continued to communicate, we started sending each other secretly filmed images via social media. I called myself ‘Hunter A,’ and I captured images of the underskirts I filmed on video at the school and sent those for which faces weren’t visible to Cobalt.”
When asked by the prosecution how he felt about associating with Cobalt, who was obsessed with female students at the school where she worked, he replied, “I had also been secretly filming, so there was a kind of twisted sense of camaraderie.”
During their communication, he revealed to Cobalt that he was a lecturer at the very girls’ school that he was obsessed with. Naturally, Cobalt requested information, but Sato testified that while he had given the names of the female students who had been secretly filmed, he hadn’t revealed their addresses.
“Extremely malicious”
In its closing argument, the prosecution stated that this was an “extremely malicious crime in which the feelings of trusted students were exploited for his own sexual desires.”
“He provided personal information and secretly filmed images of students he should have protected out of a desire for recognition from his fellow voyeurs. This is an extremely selfish reason with no room for leniency.”
The prosecution is requesting a three-year prison sentence.
On the other hand, the defense is seeking a suspended term. It argued that Sato “has already begun attending a specialized clinic and can be expected to be supervised by his relatives.”
“I could no longer control myself”
At one point, Sato recalled feeling “a sense of relief” when he was arrested. When asked by his lawyer why, he said, “I was in a state where I could no longer control myself, so I felt that this time, I had to stop.”
In his final statement, he said, “As a teacher and as a human being, I have engaged in conduct that is unacceptable. I will absolutely never repeat such a thing in the future.”
The verdict was scheduled to be handed down on March 13.
