Japan's parliament amended the imperial succession law on Friday while retaining the ban on women ascending the throne, even though public surveys indicate broad support for female monarchs.
The future of the imperial household, mythically descended from the Shinto sun goddess Amaterasu, currently depends on Prince Hisahito, the 19-year-old nephew of Emperor Naruhito, 66.
If Hisahito—an unmarried 19-year-old biology student and dragonfly enthusiast—has no son, the imperial bloodline will end under the current rules.
Although eight female emperors have historically sat on the Chrysanthemum Throne, an 1889 law stipulated that only men could ascend, strictly through the paternal line. The family's divine status was later renounced after World War II.
Carried over into the 1947 Imperial Household Law, these regulations rule out the popular Princess Aiko, 24, daughter of Naruhito, or any other royal woman, from ever becoming emperor.
The bill, passed by the upper house on Friday, allows the adoption of male distant relatives aged over 15 back into the imperial family, as long as they are single, and for their future sons to become eligible to ascend the throne. They are members of 11 families that left the imperial register after Japan's defeat in World War II.
The new rules also end the practice of forcing royal women to surrender their titles upon marrying a commoner, though their children remain barred from the throne due to their gender
The legislation was passed after wrangling within the ruling Liberal Democratic Party (LDP) led by Japan's first woman prime minister, Sanae Takaichi, who opposes female succession. Seiichiro Murakami, a veteran of the conservative LDP, said after the bill passed the lower house on July 10 that it was "utterly outrageous" to rule out Aiko becoming emperor.
Asahiro Kuni, 81, a member of one of the 11 imperial branches, has also said he would advise his grandchildren to refuse the opportunity of becoming royals. "By the age of 15, a person has grown up breathing the air of freedom," Kuni told the Asahi Shimbun daily.
A poll conducted by the Mainichi Shimbun last month found only 23% of people in favor of the sons of re-adopted imperial family members becoming emperor, and 34% against. By contrast, more than 70% supported a woman emperor, and 40% a matrilineal one.
A poll in May by the Asahi Shimbun, one of Japan's oldest national daily newspapers, also showed 72% of respondents in favor of changing the rules to allow women to ascend the throne.
The imperial family now has 16 members in total, including five men: retired Emperor Akihito, 92, his brother Prince Hitachi, 90, current Emperor Naruhito, his brother Prince Akishino, and young Prince Hisahito.
Hideya Kawanishi, a professor at Nagoya University and an expert in Japan's emperor system, said that the new bill "fails to reflect public opinion." "For the conservative camp of the ruling Liberal Democratic Party and the likes, the overriding goal is to preserve the male-line, male-only succession to the throne, and that is precisely why they do not want to listen to the voices of the people," he said. "I believe these amendments carry the risk of undermining public support for the symbolic Emperor system."
"Maybe it would have been good if they talked more about the possibility of female emperors and other stuff reflecting modern society," office worker Yoshiki Yaguchi, 66, said.
"The male chauvinism has to be scrapped,” high-school student Yumi, 17, told AFP alongside her friend Misa as they walked out of a shopping mall.