Supreme Court Bars States From Protecting Consumers From Harms by Chemical Companies

by | Jul 6, 2026 | Quick Facts

Supreme Court Bars States From Protecting Consumers From Harms by Chemical Companies

by | Jul 6, 2026 | Quick Facts

These efforts reflect concerted efforts to protect large corporations from consumers’ claims that products have harmed them and to prevent states from holding companies accountable when federal regulation falls short.

Republished with permission from The Conversation, by Sarah J. Morath, Wake Forest University

Chemical giant Monsanto has argued for years that if the U.S. Environmental Protection Agency approves a pesticide label without requiring a cancer warning, states cannot hold its manufacturer liable in court for failing to warn consumers about cancer risks. The U.S. Supreme Court agreed, in a ruling issued on June 25, 2026, though some members of Congress are taking steps to override that ruling.

Between 2009 and 2019, the EPA repeatedly concluded there is no evidence that glyphosate causes cancer in humans. The agency has, therefore, allowed glyphosate-based weed killers, including Monsanto’s Roundup, to remain on the market without a cancer warning on its label. That’s despite a 2015 report from the International Agency for Research on Cancer, a branch of the World Health Organization, that classified glyphosate as “probably carcinogenic to humans” based on “limited” evidence of cancer in humans from real-world exposure and “sufficient” evidence of cancer in experimental animals. A 2025 study had similar findings in lab rats.

Several U.S. lawsuits have used the 2015 report to win legal cases claiming that Monsanto failed to warn them of the chemical’s dangers. One of the first, Hardeman v. Monsanto Co., ended in a US$80 million verdict against Monsanto in 2019. The jury found that Edwin Hardeman, a California man who used the weed killer on his properties, had proved that Roundup had caused his cancer and that Monsanto had failed to warn consumers of the dangers of its product. That finding was upheld on appeal.

In the years since, Monsanto, now owned by German chemical giant Bayer, has paid out over $10 billion to settle about 100,000 claims from people who said their health was harmed after they were exposed to Roundup. But Monsanto continues to say—and the Supreme Court agreed—that a federal law passed in 1947 and significantly amended in 1972, the Federal Insecticide, Fungicide, and Rodenticide Act, bars states from imposing any labeling requirement beyond what the federal government has approved—meaning state courts cannot hold the company liable for failing to include a warning that the U.S. EPA does not require.

While the law was originally administered by the U.S. Department of Agriculture, today the Environmental Protection Agency regulates the registration, use and sale of pesticides in the United States. Companies that wish to sell pesticides must, according to the law, demonstrate that they will not “cause unreasonable adverse effects on the environment,” including “water, air, land, and all plants and man and other animals … and the interrelationships which exist among these.”

As a scholar of environmental and food law, I can say the Supreme Court’s decision in the case will effectively block tens of thousands of other lawsuits saying the company failed to warn consumers about glyphosate’s potential dangers. It will also raise problems for similar lawsuits against other pesticide manufacturers.

A recent proposal to settle a large number of lawsuits with a $7.25 billion class action settlement may also be reexamined.

The Durnell decision, however, is limited to failure-to-warn claims. The harms associated with pesticides will continue to be a concern for consumers, courts and legislatures.

A Short History of the Case

The case before the Supreme Court began in 2019, when John Durnell, a resident of St. Louis, sued Monsanto in a Missouri state court, claiming that his regular use of Roundup in neighborhood beautification efforts over many years had caused him to develop non-Hodgkin lymphoma, a type of blood cancer.

As it had done in previous cases, Monsanto sought to dismiss the lawsuit by claiming the federal law prevented Durnell from making those claims in state court. But the trial proceeded, and in 2023 a Missouri jury found that Monsanto had, in fact, failed to warn Durnell of the danger and awarded him $1.25 million in damages.

In February 2025, a state appeals court upheld the jury’s verdict, ruling that Missouri’s laws requiring companies to warn of dangers are not preempted by federal law. Both Missouri and federal law, the appeals court found, require companies to label products with adequate warnings to protect public health. The fact that the EPA had not required a cancer warning on Roundup did not, in the court’s view, absolve Monsanto of its separate obligation under Missouri law to warn consumers of known dangers.

The Supreme Court agreed to hear an appeal in the case, seeking to determine whether federal law bars states from holding a company liable for failing to include a warning that the EPA reviewed and chose not to require.

At the Supreme Court

During the oral argument, lawyer Paul Clement, representing Monsanto, claimed that Missouri was trying to require a different label than federal law allows, and that the company could not have added a cancer warning on its own. The company argued that EPA regulations prohibit manufacturers from changing safety warnings without the agency’s prior approval, which Monsanto never asked to do.

Principal Deputy Solicitor General Sarah Harris, a top Justice Department attorney, told the court the Trump administration agrees with Monsanto’s interpretation of the law.

Durnell’s attorney, Ashley Keller, argued that registration of a pesticide with the EPA does not exempt a company from civil liability for its product’s safety.

The justices split 7-2. In the court’s majority ruling, Justice Brett Kavanaugh wrote that the federal law specifically prevents states from requiring labels “in addition to or different from” federal labeling. And, Kavanaugh wrote, the law specifically prevents “misbranding”—the inclusion of inaccurate information on product labels. The ruling said Durnell’s claim would require a warning that the EPA did not require—but information counter to EPA’s conclusions is by definition inaccurate.

In her dissent, Justice Ketanji Brown Jackson, who was joined by Justice Neil Gorsuch, said the majority misread the federal law’s text and that Durnell’s state-law claim paralleled the federal law’s prohibition on misbranded pesticides rather than imposing an additional or different requirement. Jackson said the court’s majority ultimately made a ruling that “leaves Durnell without a remedy for the significant harms he has suffered.”

What Comes Next

The ruling in Monsanto’s favor blocks Durnell’s claim. While some Democrats in Congress say they’ll work to pass legislation undoing the ruling’s effects, other efforts are underway to defend corporations from similar claims by consumers alleging products were dangerous.

In February 2026, President Donald Trump signed an executive order calling glyphosate “crucial to the national security and defense” because of its role in boosting food production by killing weeds in farmers’ fields.

Congress is also considering a proposal that would prevent state and local governments from imposing stricter labeling requirements on pesticides than those approved by the EPA. Six states have also introduced bills to limit pesticide manufacturers’ liability. A similar provision was stripped from the Farm Bill in April 2026.

A broader legal principle is also at stake: whether Congress or federal agencies can block states from protecting people when federal regulators have not required companies to warn the public about potential harm.

In April 2026, Sen. Ted Cruz, a Texas Republican, introduced a bill that would prevent people from filing lawsuits in state courts that seek to hold oil and gas companies responsible for environmental damage, including their contributions to climate change. In late 2026 or early 2027, the Supreme Court is also expected to hear a case about whether existing federal law already blocks those lawsuits.

Together, these efforts reflect concerted efforts to protect large corporations from consumers’ claims that products have harmed them and to prevent states from holding companies accountable when federal regulation falls short.

This article includes material previously published on April 30, 2026.The Conversation

Sarah J. Morath, Professor of Law and Associate Dean for International Affairs, Wake Forest University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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