On Tuesday, the U.S. Supreme Court will hear oral arguments in Chiles v. Salazar, a case that challenges Colorado’s prohibition on licensed health professionals providing “conversion therapy” to LGBTQ children.

Here are the basic points to know:

What is conversion therapy?

As defined in a 2019 Colorado law, it’s a practice or treatment by a licensed physician aimed at changing a person’s sexual orientation or their gender identity, or to otherwise eliminate feelings of attraction toward members of the same sex. A former Republican attorney general referred to the law as a “consumer protection” statute at the time it was enacted. The American Academy of Child and Adolescent Psychiatry has concluded that conversion therapy to “lack scientific credibility” and to be harmful. There have historically been different categories of methods used, including electroshocks, hormone treatments and “talk therapy” — which is at issue in Chiles.

What is the case about?

Kaley Chiles is a licensed counselor and practicing Christian in Colorado Springs. Her lawsuit describes her as working with adults who voluntarily seek “Christian counseling” and children who are “internally motivated to seek counseling.” Chiles is arguing Colorado’s ban on conversion therapy for minors forces her to limit her speech about sexuality, for fear of violating the law.

What happened so far?

In late 2022, a trial judge declined to grant a preliminary injunction blocking the law. U.S. District Court Judge Charlotte N. Sweeney found the state was within its rights to prohibit specific treatment by those who obtain a professional license.

Last year, by 2-1, the U.S. Court of Appeals for the 10th Circuit agreed the law is a regulation on professional conduct that only “incidentally” affected speech. The dissenting judge, Harris L Hartz, believed the state is effectively regulating Chiles’ speech and he cast doubt on the scientific consensus against conversion therapy.

Didn’t the Supreme Court already address this issue?

Sort of. You may be thinking of Masterpiece Cakeshop, a 2018 case involving a Christian baker who refused to make a wedding cake for a same-sex couple. The Supreme Court didn’t answer the question of whether Colorado’s non-discrimination law unconstitutionally infringed on the baker’s exercise of his religious beliefs.

You might also be thinking of 303 Creative, a 2023 decision addressing whether a Christian website designer could decline to create wedding websites for same-sex couples and advertise that restriction accordingly. The majority determined the plaintiff’s expressive activity was protected by the First Amendment.

The same Arizona-based legal organization litigated those cases and is also litigating Chiles.

Where can I watch the arguments?

Unlike Colorado’s state courts, the U.S. Supreme Court doesn’t have a video stream of its proceedings. However, you can listen to the audio here starting at 8 a.m. Mountain time.