California’s Proposition 65 has become a poster child for ineffective and counterproductive over-warning. You know what we are talking about. Prop 65 is the voter-enacted law that requires businesses to warn Californians about significant exposures to chemicals that allegedly cause cancer or birth defects.
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The Ninth Circuit has now identified another problem with Prop 65: The required warnings are government-compelled speech, which the First Amendment protects against. In National Association of Wheat Grower v. Bonta, … a group of agricultural producers sued to enjoin California from requiring Prop 65 warnings in connection with glyphosate, the active ingredient in Roundup. There were multiple versions of the warning that the state was trying to impose, but all would have compelled the plaintiffs to post statements that glyphosate was known to cause cancer or was “listed” or “classified” as causing cancer.
The Ninth Circuit held that this violated their First Amendment right to be free from compelled speech. The core issue is that there is no scientific consensus that glyphosate is a carcinogen. The state relied on an International Agency for Research on Cancer (“IARC”) monograph classifying glyphosate as “probably carcinogenic to humans.” … But in this regard, IARC stands alone. As the Ninth Circuit observed, “While IARC has concluded that glyphosate poses some carcinogenic hazard, federal regulators, California regulators, and several international regulators have all concluded that glyphosate does not pose a carcinogenic hazard.” … Thus, not only is there no scientific consensus, the evidence overwhelming shows that glyphosate does not pose a cancer risk in humans.
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Why does this matter? It matters because compelled commercial speech is subject to intermediate scrutiny under the First Amendment, which requires the government to “directly advance” a “substantial” governmental interest, and the means chosen must not be “more extensive than necessary.”