For years, Missouri courts have been at the center of a national battle over allegations that glyphosate causes disease. Thousands of individuals have sued Monsanto, which was acquired by Bayer in 2018, in state courts across the country, claiming the company should have put a cancer warning on the herbicide’s label. On June 25, the United States Supreme Court put a stop to a large chunk of that litigation, ruling 7-2 in Monsanto Co. v. Durnell that federal law preempts any state lawsuits that required a cancer warning label for glyphosate — a warning label that the EPA itself has never required. 
The Durnell case arose out of our own courts in Missouri. John Durnell claimed he used Roundup on his property for about 20 years and was later diagnosed with non-Hodgkin’s lymphoma. He sued Monsanto in Missouri court, arguing the company had a duty under Missouri law to warn users that Roundup could cause cancer. A Missouri jury agreed and awarded Durnell $1.25 million. The Missouri Court of Appeals upheld the verdict, reasoning that Missouri’s warning requirement was essentially the same thing federal law already required.
Monsanto appealed to the U.S. Supreme Court, arguing the case never should have gone to a Missouri jury in the first place. Since 1974, the EPA has reviewed glyphosate again and again, most recently in 2020, and has consistently concluded it is not likely to cause cancer. Because of that finding, EPA has never required Roundup’s label to carry a cancer warning. Monsanto’s position was simple: If EPA says a warning isn’t required, a state jury shouldn’t get to punish the company for not including one. Associate Justice Brett Kavanaugh, writing for a seven-justice majority, agreed with Monsanto.
The key law is the Federal Insecticide, Fungicide and Rodenticide Act, known as FIFRA, which requires EPA to approve an herbicide label before the product can be sold. FIFRA contains a provision barring states from imposing labeling requirements that are “in addition to or different from” the federal requirement. The court held that once EPA approves a label, Monsanto is legally bound to use that exact label, and EPA’s approval itself counts as a federal requirement.
Durnell’s lawsuit would have forced Monsanto to add a warning that EPA specifically determined wasn’t necessary, and that is exactly the kind of additional or different state requirement FIFRA does not allow. This decision creates regulatory certainty for herbicide and pesticide manufacturers and ensures that farmers and ranchers will have ongoing access to important tools in food production. The Missouri Soybean Association and the American Soybean Association have worked hard to ensure the availability of necessary herbicides and pesticides through state and federal regulatory and legislative bodies, and this case signals a significant win. Going forward, it is clear that a single process through the EPA is the appropriate forum to raise safety concerns regarding herbicides, and the Durnell case ensures that the federal process is the only process for setting labeling requirements.
It is unlikely that the Durnell decision is the final round in the ongoing battle over glyphosate, or modern herbicides in general. While the decision is likely to focus the fight at the federal level within EPA’s regulatory process, every change in presidential administration opens the possibility of new interpretations and regulations at EPA, and every flip of control in Congress could lead to changes in the FIFRA statute itself. Producers, as always, must remain vigilant and engaged in the policy process to ensure that the safest and best food production system in the world can feed us all. Your MSA membership helps fund and equip a strong system of advocacy for Missouri soybean growers and agriculture, and it’s a good thing it does. There’s always another battle coming.
Brent Haden is the founder of Haden & Colbert in Columbia, Missouri, where he represents farmers, agricultural businesses and landowners in litigation, regulatory and property-rights matters. Raised on a farm near Mexico, Missouri, Haden earned degrees from the University of Missouri and Harvard Law School. Before founding his firm in 2011, he served as assistant counsel for the Kansas Livestock Association, represented agricultural clients in private practice, and served as chief of staff to the Kansas Speaker of the House.
