The top court of a major U.S. ally in Asia has the opportunity to issue a highly conservative ruling on a huge cultural and societal issue.

Japan's supreme court will soon address the issue of same sex marriage after an appellate court in Tokyo ruled this week that the nation's refusal to legalize such marriages was constitutional, according to the Associated Press.

Meanwhile, the U.S. Supreme Court just recently disappointed many conservatives when the justices passed on a chance to revisit the court's own 2015 decision that legalized same-sex marriages nationwide.

Prohibition upheld by appellate court

Japanese law and its constitution appear to recognize that, in order to promote childbirth and family growth, marriage can only occur between a male and female, which prompted a half a dozen lawsuits in 2019 from same-sex couples seeking the right to get married and enjoy the same benefits and protections as heterosexual couples.

The last of those six cases has now cleared the nation's "high court" level after Tokyo High Court Judge Ayumi Higashi ruled that the legal definition of a family unit -- including a husband and wife of the opposite sex, and their children -- was "rational," which therefore meant that the prohibition against same-sex marriage was "valid," per the Associated Press.

According to Kyodo News, the judge observed that the status quo was "useful" for creating a proper environment for raising children, and that it was "reasonable" to define the legal terms "husband and wife" as meaning a biological male and biological female.

The ruling further noted that the freedom of marriage enshrined in Article 24 of the Japanese Constitution did not extend to same-sex couples, and that for such couples to obtain the same benefits and protections as their heterosexual counterparts, either one partner would need to legally change their sex to get married, or that "part of the effects of marriage can be substituted by contracts."

The judge did express some concerns about the ruling being misconstrued as permitting illegal discrimination against homosexual individuals and couples and warned that additional problems could arise if parliament didn't stop stalling on legislative efforts to address the issue.

Final unified decision expected next year

Per the Kyodo News, the Tokyo High Court ruling was the only one of the six legal challenges to side in favor of the current prohibition against same-sex marriages.

It is expected that all six lawsuits will be combined on appeal to Japan's Supreme Court, with a unified decision on the matter being issued at some point next year.

Until then, and perhaps beyond, Japan will continue to be the only member of the so-called Group of Seven, or G7 countries, that has not yet legalized same-sex marriages or civil unions.

U.S. justices pass on opportunity to readdress same-sex marriage issue

Meanwhile, SCOTUSblog reported earlier this month that the U.S. Supreme Court was presented with an opportunity to revisit its 2015 decision legalizing same-sex marriages, but declined to take it up with no explanation of its reasoning.

Kim Davis, a former county clerk in Kentucky who refused for religious reasons to approve marriage licenses for same-sex couples, had asked the justices to overturn both a $100,000 civil judgment against her alongside the Obergefell v. Hodges ruling that had stemmed from a challenge against her refusal on religious grounds.

Many conservatives were disappointed by the 2015 decision, and some even more so by the more recent refusal to readdress it, particularly given the fact that the court's ideological makeup has shifted substantially more toward the conservative side over the past decade.