A court hearing has begun in western Japan in a lawsuit filed by the parents of a Maritime Self-Defense Force member who committed suicide. The parents are seeking compensation from the government, claiming harassment by superiors and long working hours caused their son to kill himself.

Nishiyama Hiroya was a leading seaman onboard a MSDF destroyer at the Sasebo base in Nagasaki Prefecture.

The 20-year-old committed suicide aboard the destroyer in February 2021.

Nishiyama was punished for drinking alcohol with his colleagues three years ago. He was still underage at the time. He was prohibited from going ashore indefinitely.

An order to keep a "self-reflection notebook" every day was given only to Nishiyama.

On the day before he took his own life, he was berated by his superiors for having made purchases at a fast food restaurant at a US navy base, despite a ban on such behavior.

In June last year, Nishiyama's loss of life was recognized as a death resulting from working excessive hours.

But the parents claim their son's suicide was caused by harassment in addition to long working hours. They say his superiors had neglected their obligation to monitor his mental and physical state. The parents sought over 77-million yen, or about 552,000 dollars, in compensation.

In the court hearing at the Sasebo Branch of the Nagasaki District Court on Wednesday, the plaintiffs argued that although Nishiyama had engaged in underage drinking, it was an abnormal disciplinary measure to make him the only target of punishment such as by ordering him to keep the self-reflection notebook.

The government has demanded that all the claims be dismissed. It said that it would clarify its position later.