At first glance, what happened in Tennessee’s legislature this spring seemed a bit odd.

Republican lawmakers introduced a bill to ban solar geoengineering — putting aerosols into the atmosphere to block some of the radiation from the sun. As climate change drives up temperatures on Earth, there is growing interest in geoengineering as a way to cool the planet. But it’s still largely theoretical, with no evidence that anyone in Tennessee is planning to try it.

The main witness to testify in support of the ban was a physician without any apparent qualifications in atmospheric science, who falsely claimed geoengineering was happening nationwide. Democrats derided the bill as ridiculous and tried to amend it with mentions of Yetis, Bigfoot and Sasquatch to prove their point.

Yet the ban sailed through the legislature. Governor Bill Lee, a Republican, signed it, making Tennessee the first state to outlaw geoengineering.

Behind the scenes, the bill was the result of lobbying by activists known in Republican circles from their efforts fighting vaccine mandates.

“We used the connections and the rapport that we had built over the last couple of years in medical freedom,” Danielle Goodrich of East Tennessee Freedom, which calls itself a “group of Patriots, Momma Bears, Conservative Christians,” explained on a podcast.