On February 26, for the first time ever, a federal district court has enjoined a California Proposition 65 warning requirement on First Amendment grounds. Under California’s Safe Drinking Water and Toxic Enforcement Act of 1986 — colloquially known as “Proposition 65” — the State listed the herbicide glyphosate, the most widely used herbicide in the world, as a chemical “known” to the State to cause cancer. California automatically listed glyphosate as a known carcinogen upon the finding by one organization, the International Agency for Research on Cancer (IARC), that glyphosate is “probably” a human carcinogen — despite contrary findings by virtually every other regulatory or research authority worldwide that has studied the question. Based on this listing, Proposition 65 requires that businesses provide a “clear and reasonable” warning to consumers before exposing them to glyphosate or products containing glyphosate. California’s regulations state that “[t]he message must clearly communicate that the chemical in question is known to the state to cause cancer.” This warning requirement for glyphosate was scheduled to take effect on July 7, 2018.

On behalf of a nationwide coalition of agricultural and business interests, Latham & Watkins filed suit against certain California officials in the United States District Court for the Eastern District of California, arguing, among other points, that the Proposition 65 warning requirement for glyphosate violates the plaintiffs’ First Amendment rights. U.S. District Judge Shubb issued a preliminary injunction prohibiting the State and anyone acting in privity or concert with the State from enforcing the glyphosate warning requirement. See Nat’l Ass’n of Wheat Growers et. al. v. Zeise et. al., No: 2:17-2401-WBS-EFB (Opinion dated Feb. 26, 2018).

Judge Shubb found that the compelled warning regarding glyphosate likely violates the plaintiffs’ First Amendment rights. The court explained that the warning is impermissible because “[i]t is inherently misleading for a warning to state that a chemical is known to the state of California to cause cancer based on the finding of one organization … when apparently all other regulatory and governmental bodies have found the opposite, including the EPA.” In other words, the warning does not pass muster under First Amendment analysis because, “given the heavy weight of evidence in the record that glyphosate is not in fact known to cause cancer, the required warning is factually inaccurate and controversial.” A reasonable consumer would not understand a substance to be “known to cause cancer,” as the warning must state, “where only one health organization had found that the substance in question causes cancer and virtually all other government agencies and health organizations that have reviewed studies on the chemical had found there was no evidence that it caused cancer.” Further, the court explained, “[p]roviding misleading or false labels to consumers also undermines California’s interest in accurately informing its citizens of health risks at the expense of plaintiffs’ First Amendment rights.” Therefore, the court preliminarily enjoined the warning requirement as to glyphosate.