The wide-ranging argument at the Supreme Court touched on the approaches of other nations, the relevance of a previous ruling protecting transgender workers from workplace discrimination and the rights of parents.

On Wednesday morning, a Nashville teenager and her parents filed into the U.S. Supreme Court along with Tennessee Gov. Bill Lee and ranking Republican lawmakers. They filled its wooden benches as the nation's top justices heard arguments in a case that could have wide-reaching impacts across the country.

The case is the first to come before the Supreme Court testing the constitutionality of laws barring transgender teens from certain gender-affirming treatments.