In Japan, divorce splits parents from children. Could a law change end sole custody?

The change in custody law offers some hope for parents like Deng who feel they have been cut off from their children.

It marks one of the most significant changes to Japan's family law in decades.

According to Japan's Ministry of Health, Labor and Welfare, around 38.5% of marriages in Japan ended in divorce in 2024 - the most recent year we have statistics for. That's roughly one in three couples.

That year, women kept custody in more than 86% of cases, while shared custody arrangements accounted for only a fraction of all agreements reached. In total, across Japan, there were more than 164,000 children under the age of 18 who had divorced parents and were impacted by custody arrangements that year.

The new law recognises that children can often benefit from maintaining relationships with both parents, while helping distribute parental responsibility more evenly.

"I'm 100% sure it's a good change to our society, especially for the children," Saito said.

"For those who are already amicable, and can make decisions together, it's very good for them to have an option to choose joint custody. I think it's a great step forward."

The change also comes as Japan faces a declining birthrate and a rapidly aging population. The demographic trend has intensified calls for the government to support families better and reduce the financial burden for single parents.

While the new law brings Japan more in line with its global peers and gives parents like Deng an opportunity to reunite with their children, it also raises serious concerns.

Critics warn that joint custody could put victims and survivors of domestic violence and abuse in bigger danger, or force continuing or renewing contact with abusive partners.

"There is a risk that those suffering from domestic violence or child abuse may be unable to escape," said Chisato Kitanaka, co-head of All Japan Women's Shelter Network.

She runs the non-profit and warns parents to fully understand the implications of joint custody arrangements in Japan, particularly in cases involving safety concerns.

For some families, shared custody raises deep, personal fears.

Taro Suzuki may now be 18, which means he is no longer under his parents' guardianship. But he says watching his mother Ryo suffer years of abuse at the hands of his father has left him traumatised. Both their names have been changed for safety.

"I wish I didn't exist in this world. I even wish my mother and father had never met, and I had never been born," Taro said. "I really think this is a law that shouldn't exist."

Ryo - who describes incidents in which her ex-husband would choke her against a wall, dangling in mid-air, and being dragged along by her hair - is also worried.

"It's really scary. When I got sole custody, I used to think, 'It'll be okay from here on out,' but now there's the possibility that we might be tied together," Ryo said.

She fears it may allow her ex-husband to reapply for joint custody of their 15-year-old daughter, pulling them back into contact.

"I really do think it's a problem. I'll have to live with that anxiety until my daughter becomes an adult."

However, there are legal protections in place for cases where there is risk of abuse or harm to a child's physical or mental well-being.

"If the court is convinced that there are domestic violence issues before the separation, before divorce, then the court must choose sole custody," Saito explained.

Still, some survivors like Ryo worry family courts in Japan will require hard evidence, and she is not convinced the courts will get all the cases right. She says in her experience, there were hardly ever physical signs of abuse because her ex-husband was cautious about leaving marks.

For now, the law sits in the middle of a delicate balance, between protecting vulnerable parents and preserving a child's relationship with both.

Back at the neighbourhood park, Deng is hopeful the new law may allow him to once again be part of his children's everyday lives.

"The fact that they're not physically here with me just makes me feel sad," he said. "It's something that no parent should face."