The Supreme Court Considers the Monsanto Glyphosate Case

Yves here. The New Lede offers a comprehensive analysis of the ongoing Supreme Court case concerning Monsanto and glyphosate. The article not only reviews courtroom filings but also explores the arguments presented to the justices and the critical questions they have raised. A significant point highlighted is that if Monsanto wins, it could undermine state regulations that mandate specific consumer disclosure standards, effectively preventing lawsuits related to warning violations that meet federal requirements.

This warning issue is far from trivial. A troubling discovery revealed that while Monsanto did not advise consumers or farmers to take stringent precautions when using glyphosate, employees applying the chemical in test fields were equipped with hazardous materials suits.

By Carey Gillam, editor-in-chief of The New Lede and former senior correspondent at Reuters (1998-2015). She authored “Whitewash – The Story of a Weed Killer, Cancer and the Corruption of Science,” which won the Rachel Carson Book Award from the Society of Environmental Journalists in 2018. Her follow-up legal thriller, “The Monsanto Papers,” was published on March 2, 2021. Originally published at The New Lede

Background on the Case

The Supreme Court recently engaged in a rigorous debate regarding pesticide regulation, questioning Monsanto’s lawyers about the legal implications of federal law overriding state rights to allow consumers to sue for product risk disclosures, such as cancer warnings.

The case, Monsanto v. Durnell, focuses on glyphosate—a widely used herbicide found in the Roundup brand and numerous other products from the former Monsanto, now part of Bayer, a German company. Glyphosate has been scientifically linked to cancer through multiple studies and was classified as a probable human carcinogen by a World Health Organization agency in 2015.

Over the past decade, Bayer has been embroiled in more than 100,000 lawsuits brought by individuals diagnosed with non-Hodgkin lymphoma who attribute their condition to glyphosate-based products. The company has paid billions in settlements and jury awards.

In the Durnell case, as in several other trials, juries found that Monsanto failed to warn users about the cancer risks associated with glyphosate.

Arguments and Positions

Monsanto maintains that its products do not cause cancer and is urging the Supreme Court to affirm that under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), it cannot be held accountable for a lack of cancer warnings if the Environmental Protection Agency (EPA) has not identified such a risk, nor mandated a warning. The EPA asserts that glyphosate is “unlikely” to be carcinogenic.

Should Monsanto prevail, it may set a precedent limiting consumers’ ability to initiate lawsuits—not just against Monsanto but against other pesticide manufacturers as well.

During the hearing, Monsanto attorney Paul Clement emphasized that FIFRA provisions clearly prevent pesticide manufacturers from modifying safety warnings without EPA approval, arguing that holding them liable for not issuing a cancer warning would contravene Congress’s intent for uniform safety labeling.

“Congress intended to ensure consistency in pesticide safety warnings,” Clement stated. “Ignoring this clear directive would open the floodgates to crippling liability and jeopardize the interests of farmers reliant on federally approved pesticides.”

Supporting Monsanto’s stance, Sarah Harris, Principal Deputy Solicitor General for the Department of Justice, argued that states cannot undermine the EPA’s regulatory process.

On the opposing side, attorney Ashley Keller contended that FIFRA does not grant the sweeping authority claimed by Monsanto and referenced significant flaws in the EPA’s registration processes. He pointed out that the EPA failed to renew its glyphosate registration within the mandated 15-year time frame, allowing issues to “slip through the cracks.”

Keller also cited that the 9th Circuit Court of Appeals had previously vacated the EPA’s findings on glyphosate due to noncompliance with established cancer risk assessment guidelines and disregard for critical studies.

Justices’ Inquiries and Public Opinion

As attorneys argued, justices raised various questions regarding how to handle labeling when new scientific evidence arises and the fairness of retroactively applying penalties for warning label deficiencies sanctioned by the EPA.

“Both parties made compelling cases,” remarked Daniel Hinkle, senior counsel for policy at the American Association for Justice, who observed the oral arguments. “They posed serious questions and showed a genuine concern for the case’s implications.”

Bayer expressed confidence that a favorable ruling could conclude ongoing litigation. Supporting Monsanto’s case, Syngenta—a Chinese-owned company—is facing similar lawsuits from thousands of individuals claiming they were not warned about research linking Syngenta’s paraquat herbicide to Parkinson’s disease.

Legal experts indicate that a ruling against state-based lawsuits could similarly restrict future cases against other pesticide manufacturers.

Following the Supreme Court hearing, Bayer released a statement commending the Court for its thoughtful consideration of FIFRA’s provisions and their implications for state label warnings. They emphasized that companies should not face penalties under state law for conforming to federal labeling standards, noting that the safety and cost-effectiveness of the nation’s food supply hinge on farmers’ and manufacturers’ reliance on federal regulators’ scientific judgments.

Protests and Legislative Actions

In tandem with the court proceedings, protesters associated with the Make America Healthy Again (MAHA) movement rallied outside the courthouse. They highlighted the Trump administration’s backing of Monsanto, with some individuals chanting “People over poison” and waving signs adorned with slogans like “Roundup the guilty” and “Make Monsanto pay.”

“It’s crucial at this moment to demonstrate our collective refusal to tolerate being poisoned any longer. These corporations must be held accountable, and it starts now,” stated Zen Honeycutt, founder of Moms Across America and a leader within MAHA.

Alexandra Munoz, an independent toxicologist participating in the protest, remarked, “I’ve reviewed the literature on glyphosate, and the evidence clearly indicates it is a carcinogen.”

U.S. Representative Chellie Pingree, a Democrat from Maine, joined the demonstration, expressing solidarity. “I’ve fought these issues for a long time. A rally in front of the Supreme Court uniting individuals from all political backgrounds against harmful substances in food and our environment is significant.”

The Supreme Court hearing coincides with ongoing discussions in the U.S. House of Representatives regarding the new Farm Bill, formally known as H.R. 7567, the Farm, Food, and National Security Act of 2026.

Last week, Pingree and U.S. Representative Thomas Massie, a Republican from Kentucky, proposed an amendment to the Farm Bill aimed at eliminating protections for chemical manufacturers like Bayer from lawsuits and preventing preemption of state and local warning labels for potentially harmful products.