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More than a decade ago, environmental activists in the U.S. made headway in a campaign against genetically modified foods when they scored ballot victories banning the planting of these foods in several California counties. More recently, starting in 2013, activists began persuading legislators in several states—notably Connecticut, Vermont, and Maine—to require that genetically modified foods carry warning labels. These victories seemed to foreshadow a wave of new state and local legislation hindering the production and sale of GMOs, or genetically modified organisms.

But now, in a turnabout, some states are pushing back against the anti-GMO movement. In recent legislative sessions, Texas, Alabama, Indiana, Michigan, Mississippi, Pennsylvania, and Tennessee have passed laws instructing agricultural officials to employ “sound science” in evaluating GMOs. Seeking to avoid a national patchwork of inconsistent state rules and regulations, Idaho and North Dakota have asked Congress to create national legislation based on the current scientific consensus on genetically modified foods.

States backing the sound-science approach clearly accept the overwhelming evidence that GMOs are safe to consume and useful, and that they boost crop production and reduce use of pesticides (by making crops innately more resistant to insects). A new form of rice created by scientists from the U.S., Sweden, and China even reduces greenhouse-gas emissions during the growing process. Scientific journals have published numerous reviews of studies on GMOs documenting that, as one report noted, “The scientific research conducted so far has not detected any significant hazards directly connected with the use of [genetically engineered] crops.” The American Medical Association, the U.S. National Academy of Sciences, the British Royal Society, and the American Association for the Advancement of Science all have found no evidence of harm to humans or the environment from these foods.

But a wide gap exists between what science tells us and what average Americans think about GMOs. A study earlier this year by the Pew Research Center and the American Association for the Advancement of Science found that while the vast majority of scientists think GMOs are safe, 57 percent of Americans believe otherwise. Environmental activists and so-called “natural food” producers have tried to seize on these unsubstantiated fears to demonize GMOs. They engineered successful campaigns in California’s Mendocino and Marin counties in 2004 that prohibited the growing of genetically engineered foods. Further bans stalled, however, and the anti-GMO groups switched strategies several years ago to advocate for mandatory labelling of genetically modified foods. After notable failures with ballot initiatives in California and Oregon, advocates won passage of laws in several states based on the argument that consumers have a right to know what’s in their food. Their hope is that if just a handful of major states enact labeling requirements, food companies will find it too expensive to create separate labeling for different locations, and America will wind up with a de facto national labeling requirement.

But even as it suggests that consumers need to know more about genetically engineered food, the mandatory-labeling campaign is fundamentally misleading. As New Hampshire state representative Linda Lauer, a Democrat and a retired chemist who opposed labelling in her state, said last year, “If there’s no health risk, then why are you requiring a label?” The labeling schemes are legally dubious, too: the U.S. Constitution explicitly grants the federal government the right to regulate interstate commerce, and individual state laws setting different standards interfere with that. In July, the House of Representatives passed legislation that would set a single federal standard for treating foods with genetically modified organisms and prohibit states from enforcing their own legislation. The courts may also have a say in the matter. Vermont’s labeling law has already prompted a lawsuit in federal court challenging its constitutionality.

Suggesting that genetically modified foods are monstrous, opponents of GMOs have called them Frankenfoods. But Mary Shelley’s Frankenstein was a fantasy—a story about resurrecting a composite body from the dead and thus defying the laws of science. Genetically modified foods, by contrast, are scientifically sound. The real problem is not with GMOs, but with the Frankenlaws that would curtail their use.