The climate case – one of three decided on Tuesday – was the first to be tested at Europe's regional human rights court. Earlier lawsuits filed over the last decade in courts around the world have mostly succeeded or failed at or below the national level.

A win at the European Court of Human Rights (ECtHR) sets a precedent for courts across the region. Given similarities to arguments made by the Swiss women who won, it also has direct implications for seven other climate cases that the ECtHR had put on hold pending Tuesday's rulings, legal experts said.

The two other cases decided on Tuesday were deemed inadmissible, and these failures may also impact pending cases.

The Swiss case ruling on Tuesday - where the court ruled that the Swiss government had violated the human rights of more than 2,000 elderly women by failing to do enough to combat climate change - served as a reminder that even human rights courts are open to arguments that challenge commitments to tackling climate change, lawyers said.

It's "going to have a significant impact on the other pending cases before the European Court," said Tom Cummins, partner at British multinational law firm Ashurst.

There are seven lawsuits pending at the ECtHR that rest their argument on the same rights violation that the Swiss case successfully argued, including two that could hit the oil industry in Norway.

Others challenge climate policies and pacts in Germany, Italy and dozens of other European states. Some focus on the specific harms they say government inaction has caused them, including one where a man with a medical condition is suing Austria because he suffers mobility issues when temperatures exceed 30 degree Celsius.

"All of these cases rely on the same provisions and same legal theories around state and government responsibility," said lawyer Sam Hunter-Jones at non-profit law firm ClientEarth.

CHILLING EFFECT

Of the seven pending cases, two are against the Norwegian government. They argue that the country's decision in 2016 to grant oil exploration licenses in the Arctic violates human rights by further committing to the release of planet-warming emissions.

A victory in either case could create "higher hurdles and costs for new exploration/extraction projects," said Laura Houët, partner and co-head of environmental, social and governance (ESG) issues at international law firm CMS. This could ultimately limit new oil and gas projects across Europe, she said.

"Understanding what might happen with the Norwegian case, and others that are pending, is crucial," Houët said.

Norway's climate minister, Andreas Bjelland Eriksen, said his government was reviewing the court's ruling against Switzerland. In 2022, Norway had asked the ECtHR to dismiss the Arctic oil lawsuit brought by NGOs, citing its role as a stable energy supplier amid the war in Ukraine.

Equinor and Aker BP, Norway's two-largest petroleum producers, have both won exploration permits in the Barents Sea. Aker BP did not immediately respond to a request for comment. Equinor declined to comment.

The International Association of Oil & Gas Producers said climate lawsuits were adding to a range of challenges facing Europe's industry, which include complex legislation and high energy costs.

"When you add climate litigation and such rulings to the list, it probably doesn't help improve Europe's attractiveness for investors," a spokesperson for the industry group said.

Plaintiffs in the cases against Norway said they felt buoyed by the ECtHR's ruling against the Swiss government, saying the verdict offered signs their cases too could win.

The Swiss verdict should "send shivers through the international oil and gas industry," said Andrew Kroglund, who leads the Norwegian Grandparents' Climate Campaign, which filed one of the lawsuits.

"We think that our case has been immensely strengthened," he said.

The other case against Norway was filed by the non-profits Greenpeace Nordic and Young Friends of the Earth Norway.

The head of Greenpeace Norway, Frode Pleym, expressed relief after Tuesday's verdicts, noting their case already had tested all national legal avenues. One of the two cases dismissed on Tuesday - a case brought by six Portuguese youth against 32 governments for their failure to rapidly cut emissions - was dismissed in part for not having done this.

A third human rights case arguing that Germany's climate plans are inadequate is also based on the Swiss case, said Jürgen Resch of the non-profit Deutsche Umwelthilfe, which filed the suit on behalf of nine teenagers and adults.

NEW HURDLES

Not all climate litigants were cheered by Tuesday's rulings. The European court's dismissal of the Portuguese case suggested several other pending cases could falter for similar reasons.

There are two lawsuits filed by Italian youths that target more than 30 governments, running the risk that they might be dismissed like the Portuguese youths' case for attempting to tackle so many jurisdictions, said climate litigation expert Joana Setzer at the London School of Economics.

And in a pending case filed in 2022, five individuals are seeking to force Austria and 11 other European countries to withdraw from the international Energy Charter Treaty, which aims to protect energy investments including fossil fuel projects.

The ECT secretariat did not respond to a request for comment.

Lawyers involved in filing that case said they were concerned by the ECtHR taking issue with the fact that the Portuguese youth had not yet exhausted all legal avenues domestically.

This may also be "relevant for our case," said lead lawyer Clementine Baldon. Though, "we can argue that domestic courts have no competence to challenge states' participation in an international treaty."