BOISE, Idaho (AP) — Idaho lawmaker Barbara Ehardt was on her evening walk back in 2018 when she was struck by worry. The longtime basketball coach had recently heard about some talented transgender athletes — a pair of high school girls from Connecticut who were regularly winning sprint championships.

What if that happened in Idaho, Ehardt wondered? Would some of the cisgender students she loved to coach be pushed to the side?

The conservative Republican representative from Idaho Falls decided she would take action, and last year Idaho passed the nation’s first ban on transgender athletes in women’s sports. The concept — which opponents say is unconstitutional, sexist and bigoted — has since spread across the country, with more than 20 states currently considering similar laws. Some, like Montana, have been aided by Ehardt in the effort.