London: The European Court of Human Rights (ECtHR) decides on Tuesday whether insufficient government action on climate change can amount to a human rights violation, in three rulings that could give legal leverage to climate activists across the continent.
The cases before the 17-judge panel in Strasbourg, France, join a growing trend of communities bringing climate lawsuits against governments with arguments resting on human rights law.
A victory in any one of them could force further national policy changes to keep countries in line with the globally agreed target of limiting warming to 1.5 degrees Celsius (2.7 Fahrenheit).
In the first, filed in 2020, six young Portuguese accuse the 32 countries that are Europe's leading emitters of greenhouse gases of failing to avert catastrophic global warming, which they say threatens their right to life. They do not ask for financial compensation, but for governments to drastically cut emissions.
More than 2,000 elderly Swiss women argue that their government's "woefully inadequate" efforts to fight the heating of the planet put them at risk of dying during heatwaves. They seek a ruling that could force Bern to cut fossil fuel emissions much faster than planned.
In the final case, Damien Carême, former mayor of the French commune of Grande-Synthe, is challenging Paris's refusal to take more ambitious measures to curtail climate change.
All three cases were heard by the ECtHR's top bench, the Grand Chamber, in 2023.
Some of the governments argue the cases are inadmissible. Switzerland has said it is not the ECtHR's job to be "supreme court" on environmental matters or to enforce climate treaties.
Climate litigation expands
A verdict in favour of the claimants could set a precedent for the 46 signatories of the European Human Rights Convention.
Depending on the ruling, countries may need to update their plans for reining in climate-warming emissions in the near term. Failure to comply could result in further national litigation, and courts could issue financial penalties.
The rulings, which cannot be appealed, are also likely to serve as a guide for the fast-growing field of climate litigation.
In the last five years, the number of climate-related court cases filed around the world has more than doubled, according to a 2023 report by the UN Environment Programme and New York's Columbia University.
"It's not like tort law that has hundreds of years of precedent," said Ruth Delbaere, legal campaigns director at global civic movement Avaaz. "This is kind of new, and so judges and courts are looking at each other."
Three other international tribunals — the International Court of Justice, the Inter-American Court of Human Rights and the International Tribunal for the Law of the Sea — are currently writing advisory opinions on states' obligations on climate change.
"This ruling will almost certainly have a ripple effect across the world, not just Europe but everywhere," Delbaere said.