Osaka High Court Declares Japan's Ban on Same-Sex Marriage Unconstitutional

Paula Gonçales
Jul 22
3 min read

Updated: Jul 22

In March 2025, the Osaka High Court ruled that Japan's legal provisions prohibiting same-sex marriage are unconstitutional. The decision overturned a 2022 judgment by the Osaka District Court and became the fifth ruling by a Japanese High Court in favor of marriage equality, following similar decisions issued in Sapporo, Tokyo, Fukuoka, and Nagoya.

The ruling arose from lawsuits filed by three same-sex couples living in different Japanese prefectures. The plaintiffs sought compensation for emotional distress, arguing that the government's refusal to recognize same-sex marriage violated the constitutional principles of equality and the freedom to marry.

At first instance, however, the Osaka District Court dismissed the claims, holding that the exclusion of same-sex couples from marriage was constitutional under Japan's 1947 Constitution. According to that decision, the Constitution contemplated marriage only as a union between a man and a woman, making the statutory prohibition legally permissible.

The Court's Reasoning

In a landmark opinion, Presiding Judge Kumiko Honda held that the lack of legal recognition for same-sex marriage "seriously undermines individual dignity and is irrational."

The Court based its reasoning primarily on two provisions of the Japanese Constitution:

Article 14(1), which guarantees equality before the law; and
Article 24(2), which requires laws governing marriage and family matters to be enacted with respect for individual dignity and the essential equality of the sexes.

The plaintiffs argued that:

"The real question is whether there is any rational basis for excluding same-sex couples from the institution of marriage."

They further maintained that:

"Legalizing same-sex marriage would make more people happy without making anyone else unhappy."

No Compensation Awarded

Although the Osaka High Court declared the marriage ban unconstitutional, it rejected the plaintiffs' request for damages.

The three couples—from the prefectures of Aichi, Kyoto, and Kagawa—had each sought compensation of ¥1 million per person for emotional harm resulting from the State's failure to recognize their marriages.

The Court concluded that monetary compensation was not warranted, noting that the Supreme Court of Japan has not yet issued a definitive nationwide ruling on the constitutionality of same-sex marriage.

The Broader Legal Landscape

Since 2019, fourteen same-sex couples have filed constitutional challenges in courts across Japan, arguing that the country's prohibition on same-sex marriage violates fundamental constitutional rights.

At the same time, many local governments have introduced partnership certificate systems for same-sex couples. While these certificates provide limited administrative recognition, they do not carry the legal status or protections of marriage, particularly with respect to inheritance rights, hospital visitation, parental recognition, and other family law matters.

Despite growing public support for marriage equality and sustained advocacy from international human rights organizations—including Human Rights Watch and Amnesty International—Japan's National Diet has yet to amend the country's marriage laws.

As a result, although an increasing number of Japanese courts have found the existing legal framework to be unconstitutional, Japan remains the only G7 country that has not yet legally recognized same-sex marriage.

Disclaimer: This article is provided for informational purposes only and does not constitute legal advice. If you require guidance regarding your specific circumstances, please consult a qualified legal professional.