A lawsuit was filed with the Tokyo District Court on Tuesday over a gender gap in the conditions for receiving survivor's pension benefits under the workers' compensation insurance system.

In the lawsuit, a 54-year-old Tokyo man whose wife died at the age of 51 argues that age and other restrictions for only men violate the Constitution, which stipulates equality under the law.

According to the complaint and other sources, the man and his wife were a working couple, but the wife died of a subarachnoid hemorrhage in June 2019. Her death was deemed work-related due to her long working hours.

The husband applied for the survivor's pension in 2023, but the head of the Hachioiji labor standards inspection office denied the application, saying that the man was ineligible because he was 49 years old at the time of his wife's death.

The workers' accident compensation insurance law stipulates that recipients of the pension are in principle spouses and children who were dependent on the income of the deceased worker. There are further restrictions on recipients other than wives, with husbands having to be at least 55 years old or disabled at the time of their wives' deaths.

The plaintiff is seeking to overturn the decision not to provide him with the survivor's pension, claiming that the male-only age requirement constitutes discriminatory treatment that is unconstitutional and invalid.

"With more women joining the workforce, families face the same hardships from work-related incidents," the man said at a news conference. "I want to be treated equally."