Five climate litigation developments that defined the first half of 2026
From a landmark human rights ruling in the Netherlands to the US Supreme Court's first-ever hearing on fossil fuel accountability, courts around the world are increasingly the last line of climate defence, and the front line of resistance.
Written by Ella Wesemann and Lea Nierlich (AllRise)
The first six months of 2026 have been among the most consequential in the history of climate litigation. Courts on three continents have issued rulings, accepted petitions, and dismissed cases in ways that will shape the legal landscape for climate accountability for years to come.
The picture is not simple. Alongside historic wins, a Dutch court ordering climate adaptation for a Caribbean island for the first time, a new cross-border damages case from Pakistan, there have been serious setbacks, including the dismissal of US municipal cases and a US Supreme Court decision that could threaten dozens of state-court lawsuits at once. And for the first time in history, the United States federal government itself has become an active legal opponent of climate action.
Here are the five developments that matter most, and why they matter for the movement.
01 The Bonaire ruling: a court orders a state to protect a vulnerable island from climate change itself
January 2026 · District Court of The Hague
On 28 January 2026, the District Court of The Hague delivered what may be the most consequential climate ruling since Urgenda. In Greenpeace Netherlands v. The State of the Netherlands, the court found that the Dutch government is violating the human rights of residents of Bonaire, a Dutch Caribbean island municipality, by failing to take adequate action on both climate mitigation and adaptation.
The court ordered the Netherlands to set legally binding intermediate emissions reduction targets on the path to net zero by 2050, and to design and implement a full climate adaptation plan specifically for Bonaire by 2030. Both orders carry legal force, they are not recommendations.
What makes this ruling historic is not just its outcome, but its legal architecture. It is the first national court judgment to apply the framework established by the European Court of Human Rights in the 2024 KlimaSeniorinnen ruling, and to do so in conjunction with the 2025 Advisory Opinion of the International Court of Justice on states' climate obligations. The court used both instruments together to assess not only whether the Netherlands was cutting emissions fast enough, but whether it was protecting its own citizens from the consequences of climate change already underway.
Crucially, it also found that the Dutch government was discriminating against Bonaire's residents by applying weaker adaptation standards to the Caribbean island than to the European Netherlands, a finding with significant implications for other states that govern vulnerable overseas territories.
Why it matters for Allrise: This is the first ruling anywhere in the world to impose a judicially enforceable climate adaptation obligation on a state, not just a mitigation one. It opens a new legal front: litigants can now argue that governments must plan and fund concrete adaptation measures for vulnerable communities, not just promise to reduce emissions. The case is directly replicable in other jurisdictions where a national government governs vulnerable territories with unequal protection.
02 The US Supreme Court agrees to hear its first climate accountability case, and could decide the fate of dozens of lawsuits
February 2026 · US Supreme Court
For years, ExxonMobil and Suncor Energy have tried to move US city and county climate lawsuits out of state courts, where they are more vulnerable to local juries and state common law, and into federal courts, where pre-emption arguments are stronger. The Supreme Court had rebuffed similar efforts twice in 2025. On 23 February 2026, it agreed to hear the case for the first time.
The central question in Suncor Energy v. Boulder County is whether federal law bars local governments from seeking damages for climate change harms in state courts. Boulder, Colorado, filed its lawsuit in 2018, arguing that the two companies knowingly promoted fossil fuels while concealing their role in causing climate change. The Colorado Supreme Court allowed the case to proceed in May 2025. The oil companies have now appealed to the highest court in the land.
More than two dozen similar lawsuits filed by cities, counties, and states, including Honolulu, New York City, San Francisco, and Baltimore, have been paused, waiting on this outcome. Billions of dollars in potential liability are at stake for the fossil fuel industry.
The Trump administration has sided with the fossil fuel companies, adding the weight of the federal government to the effort to shut down state-court climate litigation. A ruling in favour of Suncor and Exxon could effectively end the entire wave of US municipal climate accountability cases.
Why it matters for Allrise: This is the highest-stakes climate litigation moment in the United States in 2026. A decision is not expected until late 2026 or early 2027, but the Supreme Court's acceptance of the case already signals a willingness to weigh in on one of the most contested questions in climate law: can communities use their own state courts to hold fossil fuel companies accountable for local climate harms?
03 Maryland's highest court dismisses the Baltimore and Annapolis climate cases, a win for Big Oil and the Trump administration
March 2026 · Supreme Court of Maryland
In a ruling that rippled through the climate litigation community, the Supreme Court of Maryland dismissed climate lawsuits filed by Baltimore, Annapolis, and Anne Arundel County against major oil companies including BP, Chevron, ExxonMobil, CITGO, and ConocoPhillips. The cases , some filed as early as 2018, accused the companies of deceiving consumers about the dangers of burning fossil fuels and sought compensation for climate-related damages to infrastructure and public services.
The court's majority concluded that state common law did not apply to the conduct alleged, and that even if it did, the local governments had failed to state a valid claim. The ruling was shaped in part by the unusual intervention of the Trump administration's Department of Justice and 24 Republican attorneys general, who filed briefs urging dismissal and argued that state law cannot be used to regulate global emissions, a matter they say belongs exclusively to the federal government under the Clean Air Act.
The Maryland dismissal is a significant blow, but it does not end US climate accountability litigation. Cases in California, Hawaii, and other states continue, and the eventual Supreme Court ruling in the Boulder case will likely be the decisive moment for the entire field.
Why it matters for Allrise: The Maryland dismissal shows the limits of common law approaches in US state courts , at least for now, and illustrates the growing role of the federal executive as an active legal adversary to climate accountability. It also sets up a stark contrast: as European courts extend climate obligations, some US courts are contracting them. This divergence is becoming a defining feature of global climate litigation in 2026.
04 Pakistani farmers sue German companies for 2022 flood damage, climate loss and damage enters the courtroom
December 2025/ January 2026 · Regional Court of Heidelberg
In the summer of 2022, catastrophic flooding submerged roughly a third of Pakistan. More than 1,700 people died. Thirty million were affected. Millions of acres of farmland were destroyed, and total economic damages were estimated at $40 billion. Pakistan contributes less than one percent of global greenhouse gas emissions.
In December 2025, 39 farmers from Sindh, the province hardest hit by the floods, filed suit before the Regional Court of Heidelberg against RWE, one of Germany's largest energy producers, and Heidelberg Materials, a global cement manufacturer. Supported by the European Centre for Constitutional and Human Rights (ECCHR), the farmers argue that the companies' cumulative CO₂ emissions contributed materially to the conditions that caused and intensified the floods, and that they are entitled to partial compensation for the damage to their livelihoods.
The case builds directly on the legal logic of the long-running Lliuya v. RWE , in which a Peruvian farmer sued RWE over glacial melt threatening his home, but goes further: it seeks redress for damages that have already occurred, not merely harm that is anticipated. It is Pakistan's first cross-border climate damages lawsuit against corporations in the Global North.
RWE responded in January 2026, calling the lawsuit legally inadmissible and arguing that holding German companies liable for global climate damage would undermine legal certainty. Heidelberg Materials has confirmed receiving the legal notice but has not commented publicly. No ruling is expected soon, but the filing alone is a milestone.
Why it matters for Allrise: This is the most direct attempt yet to operationalise the concept of climate loss and damage in a court of law. If it proceeds and succeeds even partially, it would establish that Global North emitters can be held financially liable for specific climate disasters in the Global South, a principle with enormous implications for climate justice and the broader loss and damage agenda.
05 A government sues its own states over climate action, the rise of anti-climate litigation as a political weapon
Ongoing · H1 2026
For the first time in the history of climate litigation, the United States federal government has not merely opposed climate lawsuits as a third party, it has become a plaintiff suing states for taking climate action. Since May 2025, the Trump administration's Department of Justice has been suing states directly: first New York and Vermont, to invalidate their Climate Superfund laws, which require fossil fuel companies to pay into a fund for climate-related damages based on their historic emissions. It also sued Hawaii and Michigan to block them from filing their own climate liability lawsuits. Federal judges dismissed the Michigan and Hawaii cases in January and April 2026 respectively. The administration responded by filing a new suit against Minnesota on 4 May 2026.
The DOJ argues that states are attempting to use local law to regulate global emissions, a matter it says belongs exclusively to the federal government. If successful, the lawsuits could create what legal analysts have called a de facto nationwide federal shield against state-level climate accountability, protecting fossil fuel companies from both retrospective Superfund-style liability and prospective tort claims.
This trend is not only American. According to the Union of Concerned Scientists, roughly a quarter of all newly filed climate-related cases globally now involve arguments that work against climate goals, challenging ESG requirements, renewable energy mandates, and climate disclosure rules. Fossil fuel interests are also actively lobbying Congress for sweeping liability waivers that would permanently close the courthouse doors to climate accountability lawsuits.
Why it matters for Allrise: The weaponisation of litigation against climate action is the most structurally significant development of H1 2026. It means the movement must now fight on two fronts simultaneously: pressing forward with accountability cases while defending the legal infrastructure that makes those cases possible. For Allrise and allied organisations, understanding and countering anti-climate litigation strategies has become as important as advancing new cases.
Six months in, the picture is still not simple, but the lines are sharper. Courts remain both the last line of climate defence and the front line of resistance, exactly as they were at the start of the year. The difference is that both lines are now being tested at once. The Hague and Heidelberg show defence holding. Maryland and Washington show resistance being met with resistance of its own, from governments and fossil fuel companies fighting to close the courthouse doors entirely.
For AllRise, that is the real takeaway from H1 2026. Winning cases is no longer enough. The space to bring them has to be defended too. The second half of the year will show whether that space holds.
Disclaimer: This article was developed with the assistance of artificial intelligence (AI) tools, which were used to support research, fact-checking, and editorial review. All content has been reviewed and approved by the author(s), who remain responsible for the accuracy, interpretation, and conclusions presented.