Japan keeps male-only throne rule in succession law changes

Japan's parliament changed the imperial succession law on Friday but kept the rule that prevents women from becoming emperor, despite polls cited in the report showing broad public support for female succession.

The future of the imperial household currently depends on Prince Hisahito, the 19-year-old nephew of Emperor Naruhito, who is 66. Under the current rules, if Hisahito has no son, he will have no heir and the imperial bloodline will end.

Japan has had eight female emperors on the Chrysanthemum Throne, and the imperial family's divine status was renounced after World War II. But an 1889 imperial house law limited the throne to men in the paternal line, and that rule was carried into the 1947 Imperial Household Law. The rule excludes Princess Aiko, Naruhito's 24-year-old daughter, and other royal women from becoming emperor.

The bill passed by the upper house allows single male distant relatives aged over 15 to be adopted back into the imperial family. Their future sons would then be eligible to ascend the throne. The men come from 11 families that left the imperial register after Japan's defeat in World War II. The Imperial Household Agency says their common ancestor with the current emperor dates to the 15th century and is remote by 36 to 38 degrees of kinship.

The changes also end the rule under which women lose royal status after marrying commoners. However, because they are women, their children still cannot become emperor. Former princess Mako Komuro, Emperor Naruhito's niece and one of Hisahito's two older sisters, left the family in 2021 after marrying her university sweetheart.

The legislation followed debate inside the ruling Liberal Democratic Party, led by Prime Minister Sanae Takaichi, Japan's first woman prime minister, who opposes female succession. LDP veteran Seiichiro Murakami said after the bill passed the lower house on July 10 that excluding Aiko from the throne was “utterly outrageous”.

Asahiro Kuni, 81, a member of one of the 11 former imperial branches, has said he would advise his grandchildren to refuse any chance to become royals. He told the Asahi Shimbun that by age 15 a person has grown up with freedom, and that people might not want to join the imperial family if they understood the hardships of royal life.

A Mainichi Shimbun poll last month found 23 percent of respondents supported allowing sons of re-adopted imperial family members to become emperor, while 34 percent opposed it. More than 70 percent supported a woman emperor, and 40 percent supported a matrilineal emperor. An Asahi Shimbun poll in May found 72 percent supported changing the rules to allow women to ascend the throne.

The imperial family has 16 members, including five men: retired emperor Akihito, 92, his 90-year-old brother, Emperor Naruhito, Naruhito's brother and Prince Hisahito.

Hideya Kawanishi, a Nagoya University professor who studies Japan's emperor system, said the bill fails to reflect public opinion. He said conservatives in the ruling party want to preserve male-line, male-only succession, and he argued that the amendments risk weakening public support for the symbolic emperor system.