First in Japan: Suing the Government Over Climate Change. Over 450 Additional Plaintiffs Join 'Climate Justice Lawsuit,' Supported by Celebrities and Artists, Bringing Total to 906. Survey Reveals Impacts on Health, Mental Well-being, and Economic Activity.

The 'Climate Justice Lawsuit,' the first lawsuit in Japan to hold the government legally responsible for climate change measures, filed a second lawsuit on Thursday, April 2, 2026, with 454 new plaintiffs. Combined with the first filing last December, the total number of plaintiffs nationwide is now 906. Furthermore, a survey conducted among the plaintiffs from the first and second filings revealed that they are experiencing disruptions in their daily lives, including mental, health, and economic aspects, due to climate change.
In conjunction with the filing, a crowdfunding campaign to support this lawsuit will be launched on CALL4.



・Details: https://www.call4.jp/info.php?type=items&id=I0000167









The Spread of Climate Litigation Worldwide and Japan's Lack of Concrete Measures



For the globally progressing issues of climate change and global warming, it is necessary for nations to take a central role in implementing countermeasures. Courts around the world, in countries like the Netherlands, Germany, and South Korea, have successively ruled that national greenhouse gas reduction targets are insufficient and illegal. On July 23, 2025, the International Court of Justice (ICJ) also issued an advisory opinion stating that nations have an obligation to take measures to achieve the goal agreed upon in the 2015 Paris Agreement: to limit the global average temperature increase to less than 1.5°C compared to pre-industrial levels. However, while climate change is a human rights issue and the state has a duty to protect the rights of its citizens, the Japanese government and Diet have not been willing to seriously address this problem, leaving a situation with no concrete legal measures.



First in Japan, Suing the Government Over Climate Change. Over 900 Plaintiffs from Across the Country.
～Supported by Celebrities and Artists～



Scene from the first lawsuit filing



This lawsuit is the first in Japan to hold the government legally responsible for climate change measures, with plaintiffs residing throughout the country suing the 'state,' which has been passive in its climate change countermeasures, for damages due to the infringement of their right to a peaceful life (right to enjoy the climate).



Specifically, the lawsuit alleges that the greenhouse gas emission reduction targets set in the Global Warming Countermeasure Plan, approved by the Japanese cabinet in 2025, and in the NDC (Nationally Determined Contribution)—the action plan and reduction targets for greenhouse gases that each signatory is obligated to submit and update every five years under the Paris Agreement—are illegal because the plan was not established in a way that aligns with the 1.5°C target, and because the government has failed to legislate mid-to-long-term greenhouse gas emission reduction targets that align with the 1.5°C target (legislative inaction), thereby threatening the lives of the citizens.





◆Summary of the complaint: https://x.gd/Rs6pu





Last December, 452 plaintiffs from all over the country, including students, the elderly, and the manager of a construction company whose business is affected by rising temperatures, filed a lawsuit. Supporters include economic philosopher and author of 'Capital in the Anthropocene,' Kohei Saito, as well as artists and celebrities like Kom_I, former vocalist of the group 'Suiyoubi no Campanella.'
This time, as part of the second filing for the Climate Justice Lawsuit, over 430 new plaintiffs from across the country have joined. Similar to the first lawsuit, these individuals come from various backgrounds, including people whose lives were threatened by heatstroke, workers in primary industries, and children who will shape the future. Combined, the two lawsuits involve over 900 plaintiffs who are questioning the government's responsibility and seeking a judicial decision.





【Supporters】 (Honorifics omitted)



Kohei Saito (Economic Philosopher), Jusen Asuka (Environmental Scientist), Yurika Ayukawa (Former WWF Climate Change Officer / Professor Emeritus at Chiba University of Commerce), eri (Activist / Artist / DEPT), Tokiko Kato (Musician), Hiroyuki Kawai (Co-representative of the National Network of Lawyers for a Nuclear-Free Japan), Kom_I (Artist), Rei Shiba (Journalist), Yoshiharu Sekino (Explorer, 'Great Journey'), Shinobu Yoshioka (Non-fiction writer)





Over 450 Additional Plaintiffs Join, Bringing Total to Over 900 in Second Lawsuit Filing





After filing the second lawsuit at the Tokyo District Court on Thursday, April 2, 2026, a press conference was held at the Judicial Press Club. The following comments were made by the plaintiffs. (In no particular order, partially summarized)





・Rei Shiba (Journalist)



"The recent situation in Iran has revealed how vulnerable Japan's dependence on oil is. Climate change countermeasures will become even more important from now on. Europe has significantly expanded solar power generation, achieving over 400 GW—equivalent to dozens of nuclear power plants—in just three years since 2022. While there are issues with mega-solar projects, we should promote policies that allow for coexistence, such as models that create supplementary income for farmers by installing panels on agricultural land."








・Ms. Watanabe (Grocery Store Clerk)



"Due to my job, I feel climate change very personally. Recently, food prices have risen dramatically, and I change price tags almost every month. Some items have doubled or tripled in price, and groceries that were once staples on our dinner tables have become unaffordable. I feel every day that if climate change continues like this, it will lead directly to a food crisis."





・Mr. Hashimoto (Vegetable Farmer / Saitama Prefecture)



"The vegetables don't grow large, and it's very difficult to cultivate them. Working in the summer heat gives me a headache right away, and while I drink a lot of water to prevent heatstroke, it sometimes upsets my stomach, which is really tough.

I'm worried about how long this heat will continue. I'm 50 years old, and since farming is a profession closely tied to the land, I can't pass on farming in such a harsh environment to the next generation. Climate change is everyone's problem."







・Mr. Tanaka (Ptarmigan Researcher / Niigata Prefecture)



"The ptarmigan is a specially protected, endangered species and a rare bird that inhabits high-altitude regions. Mt. Hiuchi in Niigata Prefecture is the northernmost habitat for ptarmigans in Japan, but the alpine plants they feed on are decreasing year by year. It is said that for every 154-meter increase in altitude, the temperature drops by 1°C. A 1°C rise in average temperature means the ptarmigan's breeding area will shift 154 meters higher, becoming narrower."







・Ms. Iyoda (Environmental NGO)



"Even now in the 21st century, we continue to see new cases of Minamata disease being officially recognized and confirmed in court. The history of failures by corporations and the government is repeating itself in a different form with climate change."





Survey on Damages from Climate Change
～Impacts on Health, Mental Well-being, and Economic Activities Revealed～



A survey of the plaintiffs in this lawsuit regarding the impacts of climate change revealed disruptions in their mental and physical health, as well as their daily lives. (Number of valid responses: 245)



◆Over 60% have experienced feeling unwell due to heat. 1 in 10 reported worsening of pre-existing conditions.







◆Over 40% experience symptoms of mental stress







◆Over half reported an impact on their work, with about 20% reporting an impact on their income/sales
～The causes are high temperatures and the extremification of the climate, leading to the loss of distinct seasons～











◆Approximately 90% reported increased use and frequency of air conditioning. 1 in 4 reported installing new units or increasing the number of units









Crowdfunding Campaign Launched to Support the Climate Justice Lawsuit!





In conjunction with the second lawsuit filing, we have launched a crowdfunding campaign on CALL4 to support the Climate Justice Lawsuit. This lawsuit is a challenge to question in the judicial arena whether current climate measures are truly sufficient. We want to create a society where future generations will not have to ask, "Why didn't you do anything?" Even a small step can become a great force when many join together. We ask for your support to help spread this voice throughout society.



・Crowdfunding Details: https://www.call4.jp/info.php?type=items&id=I0000167







Additionally, upon launching, we have received a comment from Mr. Kohei Saito, author of the book 'Capital in the Anthropocene.'











Kohei Saito
(Economic Philosopher / Associate Professor at the University of Tokyo Graduate School)



I filed this lawsuit because I strongly feel that climate change is no longer a 'future problem' but is already threatening our lives and human rights. Extreme heat and heavy rains have become commonplace, and their impact weighs most heavily on children, the elderly, and those in socially vulnerable positions. On the other hand, the responsibility for causing the climate crisis and the way the damage is received are remarkably unequal. Nevertheless, the Japanese government's measures remain insufficient from both a scientific and a human rights perspective.









I felt that remaining silent in the face of this inaction would be an abdication of our responsibility to future generations. A trial is not magic that can change society overnight. Still, I believe there is meaning in citizens raising their voices and continuing to question in a legal forum, which is why I joined this lawsuit. Let's create a great wave together!