Supreme Court Sides With Monsanto in Dispute Over Weedkiller’s Alleged Cancer Risk

Agribusiness Monsanto scored a significant victory at the Supreme Court on June 25 when the justices reversed a lower court ruling that opened the company up to liability for its weedkiller Roundup.

The justices handed down a 7–2 decision in one of the most consequential decisions this year. They said that a federal law preempted state law that served as the basis for a verdict against Monsanto.

The case, Monsanto v. Durnell, involved a man, John Durnell, who was diagnosed with cancer after exposure to Roundup. A Missouri jury awarded him damages based on the idea that Monsanto had failed to follow a state law requiring warnings about risks for things like cancer.

Monsanto told the Supreme Court that the verdict was flawed because of a legal doctrine known as preemption, which says that federal law takes precedence over state law when the two conflict. In this case, Monsanto said that the federal government had already regulated Roundup’s key ingredient, glyphosate, through the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

Under that law, the Environmental Protection Agency (EPA) approved glyphosate’s use and has not required additional labeling related to cancer risks.

“Durnell’s state tort claim would require Monsanto to add a cancer warning to Roundup’s label even though federal law requires Monsanto to use the EPA-approved label without a cancer warning,” Justice Brett Kavanaugh wrote in the majority opinion.

“Because Durnell’s state tort claim would impose a pesticide labeling requirement ‘in addition to or different from’ the label required by EPA, FIFRA expressly preempts Durnell’s claim.”

The June 25 decision reversed a state appellate ruling upholding Durnell’s verdict.

Justices Neil Gorsuch and Ketanji Brown Jackson dissented from the decision.

“Ultimately, the effect of the majority’s interpretation is both remarkable and regrettable, for it unjustifiably closes the courthouse doors to state tort plaintiffs like Durnell,” Jackson wrote.

The majority and dissent disagreed over whether Durnell’s arguments created a conflict with federal law. They focused on a portion of the law that said states “shall not impose or continue in effect any requirements for labeling or packaging in addition to or different from those required.”

Jackson wrote that “FIFRA’s labeling requirements are established by statute and regulation, and those requirements are no different than the labeling duties imposed by Missouri via its failure-to-warn tort.”

Both Kavanaugh and the Trump administration, which filed an amicus brief in the case, expressed concern about uniformity in regulation across states.

Although Justice Clarence Thomas agreed with the decision and joined the majority, he also penned a concurrence to criticize FIFRA. He said that the law was constitutionally flawed in that it likely delegated too much of Congress’s power to the EPA and exceeded its authority under the commerce clause.

That portion of the Constitution gives Congress the power to “regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes.” Thomas said that the law went beyond regulating interstate commerce.

“The Act thereby purports to regulate how an individual who owns pesticide products such as Roundup can use those products, even if he bought them at a locally owned store down the street, and even if he seeks to use them in his own backyard,” he said. “Accordingly, the Act is likely unconstitutional in many applications.”