Wildlife Advocates Win Favorable CEQA Ruling in Challenge to Toxic Rodenticide

A California Court of Appeal has ruled in favor of Stanford Environmental Law Clinic client, Raptors Are The Solution, finding that the discovery of new scientific information on the rat poison diphacinone requires the state to conduct proper environmental analysis under the California Environmental Quality Act (CEQA) before deciding whether to renew the rodenticide’s registration.

Diphacinone is one of seven anticoagulant rodenticides used in California to control rat populations. But rats that ingest diphacinone and other anticoagulant rodenticides are often hunted by “non-target wildlife”—birds of prey, bobcats, coyotes, and other predators. Following new scientific evidence indicating these links, the Clinic’s client, Raptors Are The Solution (Raptors), requested in December 2017 that the California Department of Pesticide Regulation reevaluate registrations for the licenses for all seven anticoagulant rodenticides before moving forward with renewing their registrations.

The Department then placed four of the rodenticides into reevaluation, but declined to reevaluate the others—including diphacinone, among the most popular and toxic of all anticoagulant rodenticides in use. In trial court, Raptors narrowed its focus to diphacinone only, challenging the Department’s decision to renew the rodenticide without reevaluation.

The trial court ruled in the Department’s favor, but with the Clinic’s help, Raptors appealed. On appeal, Raptors argued that: 1) CEQA applied to the Department’s renewal decision; and 2) the Department had failed to fulfill CEQA’s substantive requirements when it neglected to conduct a meaningful analysis of the new science indicating diphacinone’s harmful impacts. The Department, in response, claimed that CEQA should not apply to decisions not to do something—i.e., decisions not to reevaluate.

But in a unanimous opinion, the Court sided wholeheartedly with Raptors. It said that the Department’s characterization of CEQA improperly chopped the environmental “project” at issue into small pieces, when CEQA in fact mandates that the “whole of the action” be considered. In other words, the Department’s “project” could not just be denying reevaluation in a vacuum; rather, it must be understood as the entirety of the decision to renew diphacinone without reevaluating it for adverse impacts on the environment and public health. And while CEQA may not apply to denials, it certainly applies to an affirmative renewal decision and all of its related parts.

The opinion noted that the Department instead attempted to brush aside diphacinone, first by grouping it together with two other rodenticides that were not reevaluated, and second by comparing that group solely in relation to the group of rodenticides that were reevaluated. Both moves inappropriately minimized diphacinone’s impact—which stands out as uniquely toxic, pervasive, and persistent — and neither fulfilled the department’s cumulative impacts analysis requirement under CEQA.

Wildlife Advocates Win Favorable CEQA Ruling in Challenge to Toxic Rodenticide
Watch Alana in action here.

Alana Reynolds (JD ‘23), a Stanford Environmental Law Clinic student who argued the case, called the decision “a win for informed governmental decision-making and rational treatment of science that sounds environmental alarm bells.” Sam Wallace-Perdomo (JD ‘23), who co-authored briefing on the appeal, added, “The decision vindicates the basic obligation guaranteed by CEQA that agencies must consider new environmental evidence that comes to light before reviewing and approving impactful projects.” Their work builds on that of previous Clinic students, including Rachel Bowanko (JD ‘22) and Daeyeong “Dan” Kim (JD ‘22), and on the expertise and partnership of attorney Michael Graf, who filed the initial challenge and served as co-counsel on appeal.

The Court’s reversal comes with instructions to the Department to perform a cumulative impacts analysis, to consider the particular characteristics of diphacinone that are relevant to assessing its impact on the environment, and to reconsider its decision to renew diphacinone without reevaluation informed by a CEQA-compliant analysis. The decision brings hope for improving the health and avoiding secondary poisoning of non-target wildlife populations throughout the state.