Summary
In early February 2026, the Federal Judicial Centre removed a chapter explaining climate science from the Reference Manual on Scientific Evidence. Judges used this manual to evaluate scientific testimony in U.S. courtrooms. The removal was prompted after Republican state attorneys argued that the chapter presented climate science in a manner that could influence litigation against fossil fuel companies. The chapter,
Scientists who authored the chapter have issued a public letter warning that judges no longer have a scientific baseline to verify when evaluating climate evidence. The removal raises the question of whether scientific consensus should be removed from legal reference materials just because it is politically contested.
Analysis
The Reference Manual on Scientific Evidence is a guide that judges use when managing cases that involve complex scientific and technical evidence during the description of evidence. The reference guide helps judges reach informed decisions backed by scientific knowledge. The chapter in question was authored by Jessica Wentz and Radley Horton of Columbia Law School. It defined core climate terminology, described scientific consensus on climate change, the evidence of climate change, and used attribution science to explain the human causes of climate change. The chapter explained the difference between weather and climate change, making it a beneficial tool during court decisions.
The removal of the reference will influence how judges and courts understand scientific evidence.
The decision to remove the climate chapter in the reference was led by West Virginia Attorney General JB McCuskey and Nebraska Attorney General Mike Hilgers. Lawmakers argued that the chapter is presented in a way that could bias legal outcomes, particularly in ongoing litigation against fossil fuel companies. In a statement, McKuskey said, “Bias towards left-leaning climate policies would have absolutely tipped the scales in many cases.”
Judicial Watch president Tom Fitton called the chapter “a political pamphleteering for the climate scam.”
Following the removal of the chapter, 28 co-authors of the Reference Manual issued an open letter calling the removal a “political attack.”
“Omitting the climate science chapter from the Reference Manual deprives judges of a carefully reviewed baseline explanation of the relevant science. It leaves judges without a tool to evaluate the parties’ framing, sometimes cherry-picked literature, and adversarially hired and paid witnesses,” they wrote.
The core tension lies in the gap between scientific agreement and political disagreement. Despite evidence that climate change is largely driven by human activities, climate science remains politically contested in policy and legal contexts, especially when it interacts with economic outcomes. But does that mean that legal references avoid topics that are politically sensitive?
Climate-related lawsuits are increasing in the country. For example, homeowners in Washington state have filed a landmark lawsuit against oil companies over increasing insurance premiums linked to climate change. Currently, 23 states have sued President Donald Trump’s administration for the removal of the endangerment finding in the Clean Air Act. Cases like these often rely on scientific evidence, and without the climate science chapter, judges will face greater challenges when evaluating expert claims in court. As a result, this could lead to inconsistent rulings and legal uncertainty in climate cases. Advancing Earth and Space Sciences (AGU) issues a warning about ignoring science: “Climate science is not, and should never be, a partisan issue,” and added, “Court decisions that lack access to climate science will be worse for us all.”
Engagement Resources
5 climate court battles to watch in 2026 – 5 examples of high-stakes climate court cases that would use the climate science chapter
Reference Guide on Climate Science – the chapter that was removed
EPA’s endangerment finding repeal – another example of politicians removing climate science from policy