The U.S. Supreme Court upheld a Republican-backed ban in Tennessee on gender-affirming medical care for transgender minors on Wednesday in a setback for transgender rights that could bolster efforts by states to defend other measures targeting transgender people.

The conservative Supreme Court dealt a significant blow to transgender Americans on Wednesday, issuing a sweeping decision that may have implications beyond the medical care that was at center of one of the court’s highest-profile disputes this year.

A Times examination shows how a landmark case about gender-affirming care for minors was built on flawed politics and uncertain science.