Shiori was an intern journalist when allegedly raped. She then turned the camera on the system

“The reason why I even took the case to police was that I couldn’t keep the truth hidden and twisted in myself as a journalist.”

But, she adds: “The effect of trauma is never ending. It lessens, for sure, but then you keep circling back.”

The case drew international attention due to Yamaguchi’s high profile, as the then Washington bureau chief of the Tokyo Broadcasting System, and Itō’s singular focus in keeping the spotlight trained on him and the flaws in Japan’s legal and policing systems in the face of excoriating public backlash.

But her story is less well known in Australia, where the saga faced by former Liberal staffer Brittany Higgins has dominated headlines for years. There are many factual and contextual differences between the women’s cases and their trajectories, but there is a theme that winds through both – as it has with cases the world over – about the high cost endured by women who go public with their allegations of sexual assault.

On the night of April 3, 2015, Itō met Yamaguchi at a restaurant in Tokyo after he offered to help her with her career. At the time, Itō was working as an intern at Thomson Reuters.

During the evening she felt lightheaded in the restaurant’s bathroom. She says that her next memory was waking up to Yamaguchi raping her in a room at the Sheraton Hotel. He claimed the encounter was consensual.

The documentary shows grainy CCTV footage of Itō unsteady on her feet and stumbling as Yamaguchi escorts her from a taxi through the hotel lobby.

At its core, Itō’s exposé aims to smash the “black box” – a term used by prosecutors to describe her case as one that occurred behind closed doors and could not be proven – and to highlight Japan’s broken sexual assault laws, unchanged for more than 100 years and containing no reference to consent.

That is, until last year, when the parliament changed the definition of rape to “non-consensual sexual intercourse” and raised the age of consent from 13 to 16. For Itō and other campaigners, it is only a start.

“This black box that I had wasn’t just my case. The black box is everywhere in society,” she says.

‘I’m wishing for this film to push more [people] in Japan to change the law.’

Shiori Itō

“I’m wishing for this film to push more [people] in Japan to change the law.”

The documentary navigates her journey through a criminal investigation that was abandoned by prosecutors after an arrest warrant for Yamaguchi is halted, a decision that came from within the highest ranks of Tokyo’s police department.

With no further criminal recourse, Itō decided to go public with her story in 2017 and launched civil action against Yamaguchi, and he later counter-sued. Before the documentary ends, we are told that Yamaguchi’s appeal to the Supreme Court was dismissed in July 2022. The court upheld Itō’s claim that she was raped to the civil standard and upheld the damages she was owed, but found her allegation that Yamaguchi slipped her a “date rape” drug was lacking evidence and awarded him 550,000 yen ($5800).

Throughout her journey, Itō covertly recorded conversations with police and other key players, and made video diary entries, forensically examining the people and systems that failed her and would continue failing other women unless something changed.

In one particularly heart-wrenching scene, we see Itō break down sobbing when the doorman at the Sheraton Hotel agrees to testify in court with his memory of that night – that Itō had tried to make an escape toward the hotel’s entrance and appeared to be moaning and so intoxicated that she was barely conscious.

Her crusade has been the subject of a BBC documentary, she has released a memoir (also called Black Box), and this year her own documentary screened at film festivals around the world, including Sundance – a bitter triumph that has invited many press interviews like this one, invariably stoking the trauma of that hotel room in April 2015.

“Living with it this year, talking about it a lot, it’s affecting me a lot,” she says. “A month ago, I did Vipassana – you know, 10 days of not speaking meditation, just to keep balancing myself.”

In the Q&A sessions that she has held with audiences following the documentary’s screenings, Itō also has found a form of catharsis and bonding, aware that her story has resonated with many women carrying similar scars.

“It becomes like a huge sharing therapy session, over this Q&A,” she says.

“Every time now, when people are sharing their traumatic experiences, I’m asking them, ‘What’s your coping mechanism?’, so I can take it back home or share it with others.”

With the release of Black Box Diaries, Itō wants to draw a line under this chapter of her life, not sealing off the box entirely, but not allowing it to consume her either. She has squeezed in this interview around her own freelance work. Beforehand, she interviewed a Japanese actor who had entrusted her with her own story of sexual assault at the hands of another actor.

“There are so many things coming out from that industry today,” she says.

For Itō, and sexual assault campaigners everywhere, the fight continues.

National Sexual Assault, Family & Domestic Violence Counselling Line: 1800 737 732. Crisis support can be found at Lifeline: (13 11 14 and lifeline.org.au).

Black Box Diaries screens at the Melbourne International Film Festival (MIFF) on Tuesday 13 August at ACMI 1 and Wednesday 14 August at Hoyts Melbourne Central. Director Shiori Ito is a guest of the festival and will be in attendance at both sessions of the film.

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