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

Monsanto had argued that the legal doctrine of preemption shielded it from any state-level claims.

Protesters take part in a "People vs. Poison" rally against pesticides while the Supreme Court hears a pesticide liability case in Washington on April 27, 2026. Madalina Kilroy/The Epoch Times

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.