TOKYO -- Interpretation of Article 24 of the Constitution, which stipulates that "marriage shall be based only on the mutual consent of both sexes," will be a key point of contention in lawsuits filed by same-sex couples arguing that the current system barring them from officially tying the knot is unconstitutional.
The government has not clarified its position over whether same-sex marriage is constitutional, merely saying that Article 24 does not assume same-sex marriage. The Supreme Court has never presented its interpretation of "both sexes" in the clause.
The top court, however, pointed out that Article 24 should be interpreted to mean that marriage should be based on a free and equal decision made by those concerned when it ruled in 2015 that the Civil Code provision banning separate family names for married couples was constitutional.
Citing this reasoning, the plaintiffs insist that Article 24 places emphasis on freedom of marriage, and that banning same-sex marriage constitutes a violation of the clause.
Masayuki Tanamura, professor of family law at Waseda University, takes the position that same-sex marriage can be allowed under Article 24.
He says it is possible to open the way for same-sex marriage by flexibly interpreting Article 24 rather than revising the provision, and that there will be no problem if "husband" and "wife" in the Civil Code are changed to "spouses" and "father" and "mother" to "parents."
The plaintiffs additionally argue that banning same-sex couples from marrying constitutes a violation of Article 14 of the supreme law that guarantees equality under the law.
There have been numerous lawsuits on the question of whether laws or systems run counter to the principle of equality guaranteed by the Constitution. However, there have been only 10 cases in the postwar period in which the top court ruled that specific legal provisions were unconstitutional.
There have also been cases in which the Supreme Court has changed its interpretation of the Constitution to declare previously accepted legal provisions to be unconstitutional.
In 1950, the top court ruled that a Penal Code provision stipulating that those who commit patricide were to be punished with death or life imprisonment was constitutional. The top court, however, declared the clause unconstitutional in 1973.
In a separate case, the Supreme Court in 1995 accepted the constitutionality of a Civil Code clause stating that the amount of assets children born out of wedlock could inherit from their parents was half that for those born in wedlock. In its 2013 decision, the top court ruled the provision unconstitutional.
These examples show that judicial judgments can change depending on changes in views on families and other values.
The Legislative Council, an advisory panel to the justice minister, has not held thorough debate on the issue of same-sex marriage.
One person linked to the government is skeptical, however, of whether the current system of not recognizing same sex-marriage can be ruled legislative inaction.
"Discussions calling for legislation (to open the way for same-sex marriage) may gain momentum, but it's highly questionable whether the court will rule that the legislative branch of government failed to act (to open the way for same-sex marriage)," the individual said.
A long-serving judge said courts will closely examine how far discussions on same-sex marriage have matured based on evidence submitted by both plaintiffs and the defendant.
Satoshi Kinoshita, a professor at Kansai University versed in constitutional issues, points to the possibility that the lawsuits will spur discussions on same-sex marriage, citing a lawsuit that former Hansen's disease patients filed against the government arguing that Japan's isolation policy for those with the disease was unconstitutional.
"A legal team for former Hansen's disease sufferers clarified the details of discrimination they were subjected to in the suit, leading to the judgment that the isolation policy was unconstitutional," he said. "In the latest cases, the focal point will be how far the legal team for the plaintiffs can go in clarifying how same-sex couples have been discriminated against or had their dignity violated."
In a related development, Chief Cabinet Secretary Yoshihide Suga told the Diet the government needs to cautiously consider the pros and cons of opening the way for same-sex marriage in Japan.
"Since it's an issue related to the fundamental of how families should be, extremely cautious consideration is needed," Suga told a House of Representatives Budget Committee session on Feb. 14.
With regard to the damages suits filed by same-sex couples against the government, the chief Cabinet secretary said, "I'd like to refrain from commenting on the matter as documents on the lawsuits haven't been sent to the government."
He was responding to questions by Kanako Otsuji of the opposition Constitutional Democratic Party of Japan.
(Japanese original by Naotaka Ito, City News Department; and Miyuki Fujisawa, Medical Welfare News Department)