LINCOLN, Neb. (DTN) -- Though Bayer argues federal labeling laws take precedence over state failure-to-warn laws in the Roundup herbicide lawsuit before the Supreme Court, state attorneys general in three Republican states countered that claim in an amicus brief filed with the court ahead of oral arguments set for April 27, 2026, in a case that could effectively end state lawsuits aimed at the Roundup herbicide.

Eighteen amicus briefs have been filed in the case, including from attorneys general in Texas, Florida and Ohio who take no position on the merits of the underlying claims on glyphosate.

"Amici states write instead to emphasize that these decisions should be made under state law, not by a federal agency," the states said in their brief.

"State tort law is the traditional regulatory scheme for poisonous substances, and it serves vital compensatory and deterrent purposes."

The company argues the Federal Insecticide, Fungicide and Rodenticide Act, FIFRA, takes precedence over state warning-label laws and, as a result, nullifies non-Hodgkin's lymphoma claims made by alleged cancer victims across the country.

Bayer argues that Congress's original intent of the FIFRA statute was to provide consistency in such labels across the country and that U.S. Environmental Protection Agency's label of Roundup does not stipulate cancer warnings, although it could have been required.

The AGs in Texas, Ohio and Florida said in their brief that the "erroneous preemption" of state law represents an "intrusion on state sovereignty" in violation of the constitution.

"When this Court last addressed the preemptive effects of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), it recognized an important and ongoing role for 'common-law suits to enforce the (federal) prohibition on misbranding,'" the states said.

"FIFRA 'authorizes a relatively decentralized scheme that preserves a broad role for state regulation.' Where, as in this case, state law is equivalent to the federal prohibitions on misbranding, it is not preempted. This court should adhere to that understanding of FIFRA's regulatory scheme, which respects the balance struck by Congress between state and federal authority."

Earlier this year, Bayer announced a $7.3 billion settlement that covers outstanding and future Roundup claims related to non-Hodgkin's lymphoma claims.

In addition to petitioning the U.S. Supreme Court on a Missouri state failure-to-warn case now before the court, Durnell v. Monsanto, Bayer has undertaken a plan to pass legislation in states across the country to protect its interests.

Last summer in the Durnell v. Monsanto case, the Missouri Court of Appeals joined the U.S. Court of Appeal for the Ninth and 11th circuits and state appellate courts in California and Oregon in holding that federal law does not preempt state laws. The U.S. Court of Appeals for the Third Circuit ruled the opposite in another case.

OTHER BRIEFS FILED

Briefs were also filed by farm worker groups, food safety groups, groups representing local governments, state legislators and others.

Groups led by the Center for Food Safety argue that although the U.S. Environmental Protection Agency determined glyphosate was not carcinogenic, the agency's risk assessment already was found to be unlawful and vacated by a court.

"EPA's Office of Pesticide Products is a paradigmatic example of a captured agency, which has required decades of dogged public interest litigation to force it to comply with its most basic duties," the groups said in their brief.

"EPA said it could not reach a conclusion about whether glyphosate causes the type of cancer (non-Hodgkin lymphoma) to which glyphosate is most strongly linked but nevertheless concluded that it was overall 'not likely' to cause cancer, an irreconcilable inconsistency."

A coalition of farmworker groups led by Farmworker Justice, counter Bayer arguments that a Supreme Court ruling against Bayer would harm farmers.

"If companies like Monsanto cannot be held accountable for failing to provide adequate health warnings on pesticide labels, then it is farmers and farmworkers who will suffer the consequences," the groups said in a brief.

"In the long term, precluding recovery against pesticide companies for endangering the health and safety of people who use its products will shrink the pool of those willing and able to grow the food on which we depend."

A group of former EPA officials filed a brief in favor of the plaintiff in the case, arguing that EPA's registration process for product labeling was not designed to be a final determination on whether labels are adequate.

The brief said Bayer is responsible for always maintaining FIFRA-compliant labeling and not just at the moment of approval by EPA.

"Far from hindering the objectives of the act, label-based state failure-to-warn suits applying standards that parallel FIFRA's help EPA to better do its job of protecting public safety," the former EPA officials argue.

"Petitioner never proposed to EPA a labeling amendment with a cancer warning. Under the circumstances present here, the fact that EPA approved labeling without a cancer warning cannot be understood as an implicit rejection of such a warning."

Read more on DTN:

"Bayer: EPA Label Power Trumps States," https://www.dtnpf.com/….

Todd Neeley can be reached at todd.neeley@dtn.com

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