As the climate crisis deepens, so does the urgency to hold fossil fuel companies accountable for decades of deception. Governments representing more than a quarter of the US population have filed lawsuits against major corporations including ExxonMobil, Chevron, Shell, and BP, seeking justice for the harm caused by their lies about the dangers of their products. And especially on the cusp of a new Presidential administration that has vowed to support the fossil fuel industry and nominated appointees with a blatant disregard for science, the courts will become an integral arena to advance climate justice—and a pivotal space for scientists of all disciplines to make an impact.
These lawsuits hinge on the best available science to uncover the truth and inform the courts. UCS is already working with social scientists and economists, civil engineers and health practitioners who can bring extensive expertise to multi-faceted litigation. As the fossil fuel industry spares no expense to obscure these truths, the work of scientists who engage with climate litigation is increasingly vital. They bring clarity, evidence, and credibility to a high-stakes fight where lives—and the planet—are on the line.
To help scientists of all disciplines who are thinking about getting engaged, but might not know where to start, I turned to Delta Merner, Lead Scientist for UCS’s Science Hub for Climate Litigation. Merner’s research and expertise has informed climate litigation across the globe, as she connects legal teams with technical experts and leads trainings for scientists working at the intersection of climate science and law.
AAS: What would you say to scientists who feel they don’t have the expertise or understanding to participate in climate litigation?
DM: In many ways, climate litigation isn’t actually that different from the work scientists are used to doing. At its core, we’re still asking robust questions, conducting thorough research to assess those questions, and drafting compelling documents to communicate our findings. The fundamental process remains the same—it’s just a different format and audience.
In some ways, for example, my PhD defense did prepare me with skills that translate well to the courtroom. After all, you quickly learn to stay calm and back up your claims when you have to stand in a room full of brilliant, critical people ready to poke holes in your every word.
In both cases, you’re making a claim, presenting evidence, and responding to questions or criticism. The key difference is the audience. Instead of speaking to other scientists, you’re addressing a legal community that operates with its own rules of argumentation, unique citation methods, and a distinct language for making claims.
So, while the tools and processes are familiar, adapting to this new audience requires an additional layer of thoughtfulness. You’re not just presenting facts— you’re translating complex scientific evidence into a form that meets the legal system’s standards of argumentation, while upholding scientific rigor and independence. That intersection between science and law is what makes this work so fascinating and impactful.
AAS: What was that transition into the legal arena like for you? Who did you look to for guidance and to learn from?
DM: My first time testifying in court was during my PhD program, and honestly, I had very little guidance. I didn’t fully understand how different it would be to communicate my research to a legal audience. I knew my research inside and out, and I thought that would be enough—but it quickly became clear that presenting in this context is a skill in itself. It requires not only expertise in your subject matter but also the ability to convey that knowledge in a way that resonates with the specific needs and expectations of the court.
This realization pushed me to seek guidance and learn from others. There are experts who have been doing this work for years, and generally speaking, science has been presented in US courts for a long time. For me, working through the courts felt like an opportunity to apply my research to create real-world change, but to do that effectively, I needed to broaden my perspective. I’ve learned a great deal from science communicators, organizers, researchers, and litigators who understand how to bridge the gap between science and law. Each has contributed to shaping how I approach this work and helped me find my voice in the courtroom.
Historically, however, it can be difficult to find spaces to meet and work with others in this field–that’s why UCS started the Science Hub for Climate Litigation. The Science Hub for Climate Litigation has developed a valuable community of peers where scientists, communicators, and legal experts can learn from each other—whether it’s gaining insights from those with courtroom experience or collaborating to refine how we present complex evidence to drive meaningful change.
AAS: UCS scientists often provide their scientific expertise to help inform policies. You’ve said that informing legal cases is just as critical as informing the formation of policy. Can you talk a little more about that?
DM: That’s a great question, and it’s one that gets to the heart of our work. At UCS, we see climate litigation, informed by science, as one of the most impactful tools we have to address climate change—and the evidence is clear that it’s working. The last IPCC report stated that climate-related litigation “has influenced the outcome and ambition of climate governance.” It also highlighted that “outside the formal climate policy processes, climate litigation is an important arena for various actors to confront and interact over how climate change should be governed.” In short, climate litigation is actively shaping climate action today.
Scientists have a critical role to play in this space. We can conduct robust, timely, and litigation-relevant research. We can help inform the courts through amicus briefs or other legal interventions designed to provide judges with the evidence they need to make informed decisions. And we can even step into the courtroom as expert witnesses. But engaging in litigation isn’t necessarily intuitive or straightforward for most scientists. That’s where the Science Hub for Climate Litigation comes in.
The Science Hub focuses on four key areas: catalyzing legally relevant scientific research, expanding the community of scientists and legal experts informing litigation, making robust science widely accessible, and connecting legal teams with experts. Together, these efforts create a pathway for scientists to bring their expertise into the legal arena and make a tangible impact on climate action.
AAS: First and foremost, like many of our readers, you are a researcher. Can you tell us a little more about those existing gaps in current scientific research that, if addressed, could further support climate litigation?
DM: As a researcher, I see significant opportunities for science to further inform climate litigation by addressing critical gaps. Our recent report on research areas for climate litigation highlights several key needs. For instance, attribution science remains a priority—establishing causal links between emissions, climate impacts, and specific events is essential for many cases. However, there’s a pressing need to expand this research to underrepresented regions, particularly in the Global South, where baseline data is often lacking. Developing new methods to suit these contexts can help ensure justice is accessible to all communities impacted by climate change.
We also identified the connections between climate change and human health as another priority. Cases that focus on health impacts, such as those related to extreme heat or air quality, require more robust data, particularly for vulnerable populations like children, older adults, and pregnant people. Similarly, economic research that quantifies the costs of climate impacts and the benefits of mitigation is vital for informing remedies in legal cases. Addressing these issues demonstrates how expertise from diverse disciplines—whether in public health, economics, or social science—can play an important role to inform climate litigation. You don’t need to be a climate scientist to make a meaningful impact.
Beyond these priorities, our work highlights strategic areas like disinformation and greenwashing, emissions accounting, and fair share analysis for corporate and national accountability. Each of these areas presents opportunities for science to fill evidence gaps that are critical to informing litigation.
By addressing these gaps, scientists can play a role in informing the evolving landscape of climate litigation and ensure that courts have the best available science to inform their decisions.
AAS: In a recent blog post, you mentioned the opportunities to expand the scope of climate litigation in 2025. Could you elaborate on the stakes of what’s on the docket this year?
DM: This year’s climate litigation docket has high stakes, with cases that could set major precedents for how we address the climate crisis. On the international stage, the International Court of Justice (ICJ) is working on an advisory opinion to clarify what responsibilities countries have under international law to combat climate change. (UCS actually helped a number of states in the Global South to prepare draft their written submissions.) While this opinion won’t be legally binding, it could influence future cases and push governments to take stronger climate action. Similarly, the Inter-American Court of Human Rights is considering how climate change disproportionately affects vulnerable populations, linking climate action to fundamental human rights.
In the US, more than a quarter of people now live in places that are suing major fossil fuel corporations for deceiving people about climate change and for the damage they knew their oil, gas, and coal products would cause. These cases aim to hold companies accountable for the disinformation that has blocked climate action and slowed the transition to clean energy. ExxonMobil and other major fossil fuel corporations have employed numerous procedural tactics to delay progress of these lawsuits (some of which have been ongoing for more than seven years), preventing them from being heard in courtrooms across the country.
We’re also seeing more lawsuits following climate-related disasters, like the Maui wildfires and severe flooding in North Carolina. These cases often focus on holding governments or companies accountable for not doing enough to prepare for foreseeable climate risks, like stronger storms or longer droughts. They highlight the very real human and financial costs of climate inaction and aim to drive systemic change.
This wave of litigation shows that courts are becoming a critical arena for climate action, especially as political systems struggle to keep up with the urgency of the crisis. By combining evidence from science, law, and lived experience, these cases have the power to bring about accountability and push for meaningful solutions.
AAS: And I’ll close with this: it’s a new year, a fresh start, and folks are making resolutions. What is something concrete that you’re working on?
DM: This year, I’m focusing on communicating the value and potential impact of scientists informing climate litigation. It’s crucial for scientists to understand that this work is about ensuring that courts have access to accurate, robust evidence to make informed decisions. Upholding the integrity of our research while making it actionable is essential to bridging the gap between science and justice.
At the same time, I want to increase engagement among scientists to help them recognize the critical role they can play in legal processes. Whether it’s providing expert testimony, contributing to amicus briefs, or making their findings more accessible to legal teams, there are so many ways to contribute. By supporting scientists in these efforts, we can create a stronger connection between science and the legal system, and empower courts to drive meaningful change.
→ Learn more and join the UCS Science Hub for Climate Litigation today