Twenty states and Washington, DC sue over weakened US endangered-species rules

States challenge three regulatory changes

Attorneys general representing 20 US states and Washington, DC filed two lawsuits on Wednesday seeking to overturn Trump administration rules that reduce federal protections under the Endangered Species Act. The complaints target actions by the Fish and Wildlife Service and National Marine Fisheries Service. The central dispute is whether the agencies brought implementation closer to the statute’s text or unlawfully stripped away protections that Congress intended endangered and threatened wildlife to receive.

One case challenges a narrower regulatory definition of harm. Under the disputed approach, development such as drilling or mining may disturb protected habitat without automatically constituting harm unless it directly kills or injures animals. The plaintiff states argue that habitat destruction can injure wildlife even when machinery is not aimed at an individual animal, making the definition consequential for land-use approvals, energy development and conservation enforcement.

Threatened species and critical habitat

The second lawsuit contests two additional rules. One ends broad automatic protections for newly listed threatened species unless federal officials create species-specific safeguards. The other changes the process for designating critical habitat by requiring agencies to weigh objections that include economic burdens asserted by developers and other businesses. Together, the states say, those measures make protection slower and leave vulnerable species exposed during regulatory gaps.

The administration rejects that interpretation. Federal officials argue that earlier implementation expanded the law beyond authority granted by Congress and impeded projects, competitiveness and national-security priorities. The White House’s own recent ranching order illustrates the policy direction: it requires a review of federal rules affecting ranchers and directs the Interior Department to determine whether gray and Mexican wolves meet criteria for reduced or removed federal protection.

The courts will define the agencies’ room to manoeuvre

The Endangered Species Act, enacted in 1973, has been credited with helping prevent the disappearance of species including the bald eagle, California condor, grizzly bear and humpback whale. The lawsuits arrive after the Supreme Court’s 2024 decision limiting automatic judicial deference to agencies’ interpretations of ambiguous statutes. That shift gives judges a larger role in deciding which reading of the act is legally correct.

The immediate question is whether courts in the San Francisco area will block the rules while litigation proceeds. Longer term, the cases could determine how much habitat damage qualifies as prohibited harm and how quickly newly threatened species receive protection. The outcome will also affect planning certainty for mining, energy and construction projects. Until judges rule, claims that the changes are either unlawful destruction or a lawful correction remain the opposing parties’ positions, not established findings.