In around spring of 2012, Shinzo Abe -- the current prime minister who was then a legislator of the opposition Liberal Democratic Party (LDP) under the Democratic Party of Japan (DPJ)-led administration -- expressed frustration about the government's handling of the Imperial succession issue. "Is the Imperial Household Agency serious about enabling members of the former Imperial Family branches to return to the Imperial Family?" he asked.
Abe's question came during an informal study meeting that the LDP held at a hotel in Tokyo, where more than 10 attendants including LDP legislators discussed the declining number of Imperial Family members in line to the throne. The participants deliberated on proposals including one to bring male-line males in 11 former Imperial Family branches back to the Imperial household, in order to maintain Imperial succession by males with patrilineal lineage. Such members were forced to leave the Imperial Family in 1947 under the rules of the Allied Powers General Headquarters following the end of World War II.
At the end of January 2012, Abe attended meetings with members of the former Imperial Family branches to explore the possibility of their return to the Imperial Family. Behind Abe's frustration apparently lay a sense of crisis over the argument for allowing female members to retain Imperial Family status even after marriage. At the time, the DPJ administration was considering allowing the establishment of Imperial Family branches headed by married female members. Conservative lawmakers were wary of the move, with one saying, "If Imperial Family branches headed by female members are allowed, female members could in the future become empresses regnant or produce matrilineal emperors."
In the February 2012 edition of the Bungei Shunju monthly magazine, Abe stated that allowing Imperial Family branches headed by female members could fundamentally overturn the traditional process of Imperial succession. After Abe returned to the premiership in December that year following the LDP's victory in a general election, he brought the issue back to the drawing board.
The Imperial succession by male-line males, upheld since the Meiji era, was not something that had gone unchallenged. An ad-hoc research council on the legal system, which served as an advisory panel to the Cabinet that started discussing the current Imperial House Act in July 1946, debated whether to allow for an empress regnant -- also sometimes called a "female emperor." It reasoned that the postwar Constitution provides for gender equality.
The then Imperial Household Ministry offered the view that Imperial succession only by male-line males would not run counter to gender equality guaranteed under the Constitution because the Imperial Family was an exception. However, in the then Imperial Diet, many legislators pointed out the inconsistency between male-only Imperial succession and the supreme law.
"When I read the Imperial House Act, I can't help feeling that the Imperial Family stands out from the people," said Ito Niizuma, a legislator of the Social Democratic Party of Japan, during a House of Representatives session in December 1946. Niizuma was elected to the Diet in April that year -- the year when Japanese women were franchised in national politics. Citing gender equality under the postwar Constitution, Niizuma continued, "As women appear to have become equal to human beings, I wonder if they can somehow eliminate the 'male-line male' rule."
One legislator from the then National Party also told the Diet, "Japan could leave a very good impression on the international community if a possibility was left in the law to allow for an empress regnant as the symbol of a pacifist nation."
In response, then Minister of State Tokujiro Kanamori said, "We have no choice but to recognize the legitimacy of the conventional system that has been in place for many years and to keep carrying it out." His reply was an apparent attempt to sidestep in-depth debate over the compatibility of the male-only succession rule with the new Constitution. "It is almost the Japanese people's conviction that the Imperial Throne must be succeeded by male-line males," he added.
Because there were still many young male members within the Imperial Family, the minister shelved the issue, saying, "As there is no practical need to solve the issue (of a female emperor), I would like to entrust the whole matter to in-depth research in the future."
Arguments for allowing an empress regnant also did exist during the process to institute the former Imperial House Law in the Meiji era. The law, however, ended up stating for the first time that only male-line males could succeed to the throne.
The Genroin (chamber of elders), a legislative body in the Meiji era, was open to the possibility of women ascending to the Imperial Throne. It noted, "Males are prioritized over females in the same family and elders are prioritized over juniors in the same kindred." Among the draft constitutions drawn up by private citizens amid the freedom and civil rights movement in the late 19th century, many also allowed for a "female emperor" in case there was no male in line to the throne.
Isao Tokoro, professor emeritus at Kyoto Sangyo University, said, "According to ancient history books and laws and regulations, the existence of an empress has been officially recognized and appreciated in Japan. It is not a traditional Japanese way of thinking to exclude women." He continued, "(The Imperial Family) could decline and fall in the future if the government keeps regarding it as special and sticks to the current system, while emphasizing gender equality in society at large."
The constitutional principle of equality of the sexes has taken root in Japanese society and the public today finds it rather unnatural for the Imperial Family alone to attach weight to the births of male members.
According to the Japan Association for Public Opinion Research, a survey in 1975 found 31.9 percent of respondents open to the idea of am empress regnant. The figure climbed to 83.5 percent in a 2005 poll. In a November 2016 survey, 85 percent of respondents approved of an empress regnant or a matrilineal emperor. Over the past years, female Imperial Family members, including Crown Princess Masako, have attracted sympathy from the public due to the pressure they experience to give birth to boys as future heirs to the Chrysanthemum Throne.
Beate Sirota Gordon (1923-2012), an American woman who served as a staff member of the Allied Powers General Headquarters, authored the gender equality provision in the postwar Constitution to protect the rights of Japanese women, who had no right to property under the traditional patriarchal system.
Makiko Hiraoka, 70, who covered Gordon's activities for many years, told the Mainichi Shimbun, "Beate was surprised to learn the prewar Japanese custom of men divorcing their wives if they didn't give birth to any boy. I wonder why only the emperor's family is still bound by regulations."
Many members of the public are uncomfortable about the current Imperial succession system partly because Imperial Family members have tried to transform themselves into figures more familiar to the public, to live up to the postwar Constitution. A former government official who negotiated with the Imperial Household Agency over the issue of a female or matrilineal emperor under the government of Prime Minister Junichiro Koizumi surmised the feelings of Emperor Akihito, saying, "As he has made his own efforts to form the image of an emperor as the symbol of the state and of the unity of the people, he wouldn't hope for former Imperial Family members who have long been away from the Imperial household to succeed to the throne just because they are male-line males."