Teppei Kasai

Tomoya Asanuma, a prominent transgender activist in Tokyo, faced the triple abuses of Japan’s “hostage justice” system, hostile detention conditions, and mistreatment trans people face in the absence of meaningful legal protections.

For Asanuma, March 14, 2024, was supposed to be another Thursday at work. At around 7 a.m., he woke up to the sound of someone repeatedly ringing his doorbell. Through the intercom, Asanuma saw three men wearing dark-colored clothes, this time pounding his front door. When he opened the door, the men identified themselves as police officers and showed him an arrest warrant.

This was the beginning of what Asanuma recently described to Human Rights Watch as being “difficult to put into words.” After Japanese police arrested him for sexual assault for allegedly hugging an acquaintance from behind, the authorities held him for months at a pre-trial detention center.

During this time, they mocked his transgender identity during interrogation, denied him access to medical services such as dental care, and initially denied hormone treatment until he obtained a recommendation from a doctor.

While some authorities showed a level of consideration for Asanuma, including letting him shower away from other detained men, the abusive treatment he faced led him to attempt suicide twice.

Trans people in Japan are in legal limbo. Historically, they have faced outright discrimination — including a law compelling them to be surgically sterilized for legal gender recognition — and barriers to accessing education, employment, and health care. A landmark Supreme Court decision in 2023 declared the sterilization requirement unconstitutional, but reform has stalled in parliament — leaving trans people’s basic rights in limbo.

The courts finally granted bail to Asanuma in July 2024 and found him not guilty in January 2025. But in a country with a 99.8 percent conviction rate for indicted cases, Asanuma had to live through acute fear as authorities forcibly tried to obtain a confession from him during interrogations without the presence of his lawyer.

His fears are grounded in a justice system with a well-earned reputation for abuse and arbitrariness. His experience is part of systemic treatment in Japan called “hostage justice,” under which criminal suspects are detained for prolonged periods, sometimes months or years, unless they confess to the charges. This denies them the rights to due process and a fair trial.

The authorities ultimately dropped the sexual assault allegations, but charged Asanuma with assault, which is punishable by up to two years in prison or up to a 300,000 yen fine ($2,000.) Prosecutors sought a 200,000 yen fine. Despite this, because he pleaded not guilty, a court rejected his request for bail four times and detained him for more than 100 days in pre-trial detention, punishing him disproportionately since the prosecutors did not even seek imprisonment for his alleged crime.

In Japan’s hostage justice system, authorities frequently subject suspects to harsh interrogations to coerce confessions from them during pre-indictment detention. Defense lawyers are not permitted to be present, and the questioning does not stop even when a suspect invokes their constitutional right to remain silent. Indeed, Asanuma invoked his right to remain silent, but authorities interrogated him for hours on 13 occasions.

The case of Iwao Hakamata highlights the dangers of this practice. Hakamata, a former professional boxer, was arrested on Aug. 18, 1966, for murdering a family of four. Following harsh interrogations by the police and prosecutors, he confessed nearly a month later. Based on this coerced confession, Hakamata was indicted and subsequently convicted and sentenced to death. He maintained his innocence and was eventually acquitted — 58 years after his arrest — on Sept. 26, 2024, following a retrial.

To prevent further abuses and wrongful convictions spurred by the “hostage justice” system, the Japanese government should not as a general rule deny bail to suspects in pretrial detention, and should end interrogations without legal counsel that often involve coerced confessions through manipulation and intimidation.

The Japanese government should also improve the conditions under which suspects are being held, including by ensuring adequate access to all medical services, and revising the Notice Regarding Treatment Guidelines for Detainees with Gender Identity Disorder by specifying that hormone replacement therapy and other gender-affirming medical interventions are medically necessary and should be made available to all imprisoned people who want them.

“My case is just the tip of the iceberg, as there are others who are detained much longer,” Asanuma said. “I think this experience gave me a good reason to speak up even more for the rights of suspects going forward,” he added.