
After a decade, Peruvian mountain guide Saúl Luciano Lliuya’s lawsuit against German energy company RWE has finally reached a close: a loss for Lliuya, but a win for climate litigators. In a landmark decision, the Higher Regional Court of Hamm, Germany, concluded that greenhouse gas-emitting corporations could be liable for climate change-induced damages—even those suffered continents away.
The lawsuit stems from events in 1941, when a flood devastated the small mountain town of Huaraz in the Peruvian Andes. A massive landslide from the face of the Palcaraju Glacier fell into Lake Palcacocha above the town, sending forth a gush of water that tore down the valley and killed at least 1800 people.
As warming temperatures have caused the Palcaraju Glacier to melt faster, Huaraz residents—who have quintupled to a population of 120,0000—fear another glacial lake outburst flood (GLOF). To protect his home, Indigenous Huaraz resident Lliuya built a dike, and in 2015, decided to sue those responsible for the costs. But who is responsible for a melting glacier? For Lliuya, backed by the nonprofit organization Germanwatch, one answer was RWE, a German energy company and leading greenhouse gas emitter. Lliuya sued for 0.5% of the dike’s costs, the same proportion as RWE’s contribution to worldwide emissions.
Ten years later, the German court dismissed Lliuya’s suit because it deemed the risk to be of insufficient scale and certainty, with no opportunity to appeal. While Lliuya’s scientific experts found a 30 percent chance of a GLOF in the next 30 years, the court-appointed experts surveyed the area and found only a one percent risk—not enough for RWE to pay the $17,000 euros that Lliuya was asking for. “He basically lost because he lives 50 feet too far away from the river,” said Noah Walker-Crawford, a former climate litigation advisor at Germanwatch who has worked on the case since its inception. Other Huaraz residents who live next to the river face a higher risk of GLOFs. Some “have already come forward saying they want to bring claims of their own,” added Walker-Crawford.
This difference in expert opinion has been controversial. The court-appointed experts’ findings were met with “a lot of critique from the scientific community,” said Walker-Crawford. The experts excluded rockfalls from their consideration of future GLOFs and used past data to predict future risk, not considering climate change’s accelerated melting that could make such floods more likely.
But despite the loss for Lliuya, it was a landmark ruling for climate litigators. The court spelled out in detail that RWE could be held liable for emission-induced climate change damages. “With the processes of climate change, it’s a very clear causal link. In legal terms, it’s basic property rights,” said Walker-Crawford.
While simple, the decision was groundbreaking: it was the first time a court affirmed corporate accountability for climate damages. “It has changed the climate litigation landscape forever,” said Mónica Feria-Tinta, a British-Peruvian expert in public international law at Twenty Essex, in an interview with GlacierHub.
The transboundary case looked to the international historical precedent of the 1938 Trail Smelter Case, in which Canadian polluters had to pay for damage caused in the United States. Lliuya v. RWE took this a step further: Peru and Germany are not just separate nations, but thousands of miles apart. Still, the polluter pays principle applied. As Feria-Tinta said, climate change “doesn’t respect borders. It goes beyond jurisdictions.”
Furthermore, the case has raised Huaraz and glaciers to a new level of international cognizance. Already, communities in the high Andes are facing drought, unreliable growing seasons and pasture loss. “When I had a conversation with Lliuya, he explained to me that this was not just glaciers, but that all of these changes were deeply interrelated,” said Feria-Tinta. In the broader fight for climate justice, Lliuya has been “a symbolic representative” for Peruvians, said Walker-Crawford. Locally and nationally, the verdict has been received as “a big success.”

The effects reverberate beyond Peru, too. “This is not a Peruvian issue. This is fundamentally a global issue,” said Feria-Tinta. Indeed, a 2023 study published in Nature Communications found that 15 million people are exposed to potential GLOFs. Globally, glaciers are melting and retreating, threatening communities with floods or water shortages. Now, based on Lliuya’s precedent, communities can seek accountability from corporations located continents away.
Already, before the verdict was even settled, the international headlines sparked by Lliuya v. RWE have caused corporations and insurers to take note. “All of these developments are watched,” said Feria-Tinta, “they can’t just operate as business as usual.” Of course, if Lliuya had won, it would have been the first time a fossil fuel company paid for climate damages and would have “made a bigger splash,” said Michael Burger, executive director of the Sabin Center for Climate Change Law, which is part of the Columbia Climate School.
Instead, the case will only offer a non-binding comparative precedent for courts to consider. Still, in the young realm of climate litigation, this could prove important. “Climate change isn’t an issue that courts have been dealing with for very long,” said Walker-Crawford, “so we’ve seen already in the past that judges will look to what courts are doing in other countries.” Within the U.S., the effect might be less direct. According to Michael Gerrard, the founder and faculty director of the Sabin Center, “U.S. courts tend not to cite foreign decisions, so I don’t think this case will affect U.S. climate law.”
While its direct influence on U.S. judicial proceedings is unlikely, the lawsuit’s high profile has motivated similar cases in the country. In the last five years, various communities, cities and states have brought a wave of lawsuits against fossil fuel companies. For example, the town of Carrboro, North Carolina, is suing Duke Energy for current and future damages caused by climate change through floods and heat waves. Over 20 other cases are also pending against fossil fuel companies. Payouts could reach into the billions.
There are cases across national borders as well, which could have more to draw from Lliuya’s precedent. Notably, in Asmani et al. v. Holcim, four residents of the island of Pari, Indonesia, are suing the historically large carbon emitter Holcim, a Swiss building materials company. The case, which was filed in 2022, requests money both for damages and for emissions reduction.
A day after the Lliuya decision, debris from a collapsing glacier crushed an entire mountain town in Switzerland. No lives were lost because the residents had been evacuated days before. For Feria-Tinta, this event exposed a deep climate injustice. A wealthy country like Switzerland was able to monitor the nearly imperceptible glacial changes and save lives, but other remote, poorer high mountain communities like Huaraz might not “have that same ability.”
Lliuya’s high-profile lawsuit has begun to raise this inequality to international attention. The true legacy of this case is perhaps best encapsulated by Lliuya himself, who said in a statement after the decision: “This ruling opens the doors for others to demand justice.”