Climate lawsuit Saúl vs RWE: “A historic ruling that can serve as a guide for courts around the world” – Interview

In principle, large emitters can be held accountable for climate risks. This was the ruling handed down by the Higher Regional Court on May 28 in the climate lawsuit brought by Saúl Luciano Lliuya against RWE. The court has thus made legal history. However, Saúl’s lawsuit was dismissed because the court did not consider the flood risk to his property to be sufficiently high. Francesca Mascha Klein, legal advisor for strategic litigation, has accompanied the proceedings and explains in this interview why the ruling is an important precedent.

Before we look at the ruling, could you briefly describe what this case was about?

Francesca Mascha Klein: Saúl’s lawsuit sought to hold one of Europe’s largest emitters, RWE, accountable for its emissions. Saúl demanded that the company contribute to protective measures at a glacial lake above the city of Huaraz that had reached a dangerous size. RWE’s emissions contribute to the risk of a flood wave, so the company should pay a share of the costs for protective measures.

After almost ten years of legal proceedings, the Higher Regional Court of Hamm handed down its ruling in May. What exactly did the court decide?

Francesca Mascha Klein: The court ruled that large emitters can be held accountable under German civil law. In a ruling spanning more than 50 pages, the court explains why Saúl’s claim is legally valid. This means that those affected can now take legal action to demand that major polluters share the costs of climate change impacts – even across national borders. This is a legal milestone.

Why was the lawsuit dismissed nonetheless?

Francesca Mascha Klein: According to the Civil Senate, it could not be proven in this specific case that Saúl Luciano Lliuya’s house and property would be affected by a glacier flood with a sufficiently high degree of probability.

The court followed the expert opinion on the flood risk submitted by court experts in the summer of 2024, which was the focus of the oral hearing in March 2025. The court experts estimated the probability of a glacial lake outburst flood (GLOF) reaching Saúl Luciano Lliuya’s property in the next thirty years at one percent. The experts based their assessment on past events and extrapolated them to the future. They did not take into account rockfalls as a trigger for a flood wave or the fact that these are occurring more frequently as the climate crisis progresses. Supported by experts in climate and glacier science, the plaintiffs had argued that there was a high risk of flooding, particularly due to climate change. However, the court did not agree and therefore dismissed the lawsuit.

How did Saúl experience the verdict?

Francesca Mascha Klein: Saúl was with his family in Huaraz when the verdict was announced. We kept him up to date via WhatsApp. He was very happy about this groundbreaking ruling! Of course, he was a little disappointed that the court dismissed his lawsuit. But for him, it was clear that he wanted not only to win his individual case, but also to strengthen the rights of all people exposed to the dangers of the climate crisis against those responsible. In this respect, his efforts were successful.

Companies like RWE argue that climate change is too complex and that responsibility cannot simply be attributed to individual companies. What did the judges have to say about this?

Francesca Mascha Klein: In their ruling, the judges refuted numerous arguments put forward by the fossil fuel industry. This included the argument that climate change is too complex to hold individual companies liable.

The court made it clear that Saúl’s lawsuit concerns clearly identifiable CO₂ emissions whose global impact is scientifically proven and traceable. According to the Carbon Majors study, RWE is responsible for around 0.4% of man-made global warming. The court recognized that RWE’s contribution is significant — comparable to that of entire industrialized countries such as Sweden or Spain. Those who contribute significantly to the climate crisis must take responsibility. This is in line with the polluter pays principle and, in the court’s view, an expression of a “value-based legal order.”

Do you expect more lawsuits of a similar nature now?

Francesca Mascha Klein: Those affected by the climate crisis can now hold major polluters legally accountable. Similar regulations to those in Germany also exist in other countries. According to our research, there are comparable regulations in at least 15 countries, including Switzerland and Japan. Thanks to advances in climate science, it is possible to prove causal links with increasing accuracy. People from all over the world followed the case. There will certainly be similar lawsuits in other countries.

Does the ruling have implications for politics too?

Francesca Mascha Klein: This case made one thing clear: companies that have profited from climate-damaging business models for decades do not pay the price of the climate crisis. Instead, those affected in the Global South and countries with historically low emissions bear a large part of the burden. Political decision-makers now have the opportunity to ensure clarity and justice by establishing binding regulations on how affected parties can be compensated and how companies with high emissions can be held accountable for the consequences of the climate crisis. Examples of such regulations exist in the Philippines and in some US states. Now it is Germany’s turn.

What does the future hold for Saúl and the people of Huaraz?

Francesca Mascha Klein: The situation in Huaraz is serious. The consequences of climate change have long been a reality: rockfalls and avalanches are occurring more and more frequently, and two people were recently killed in a landslide in the region. But Saúl, the local NGO Wayintsik Perú, and we at Germanwatch are staying on the case. Saúl is reviewing the ruling and possible next legal steps with his lawyer, Dr. Roda Verheyen. We remain active on the political front as well: Germanwatch will continue to highlight the significance of this case, particularly in the context of international climate negotiations, and will campaign for the rights and protection of those particularly affected.

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