Dr Paul Behrens as amicus curiae at the US Supreme Court

In August 2025, the US Supreme Court published the amicus curiae brief (an expert opinion to assist the Court in its considerations), by Dr Paul Behrens, Reader in Law at Edinburgh Law School, in the case of Chiles v Salazar, in its docket.

The case concerns Colorado's 'minor conversion therapy law'. Conversion 'therapies', or conversion practices, seek to change a person's sexual orientation, gender identity, or gender expression. Usually, these are attempts to turn gay people 'straight' or to make transgender people cisgender. Such practices lack scientific basis and can cause considerable harm, including self-hatred, shame, guilt, post-traumatic stress disorder, and suicidal ideation. Those subjected to these practices are often children. Many medical associations oppose these methods and an increasing number of States have prohibited them. In other places, including the United Kingdom, such laws are still under consideration. Dr Behrens was, in 2022, a member of the Expert Advisory Group to the Scottish Government, which submitted a report and recommendations for a comprehensive ban.

The key argument in Dr Behrens' brief is that the Colorado conversion therapy law targets professional conduct, not protected speech, since conversion practices are both medically harmful and scientifically discredited. He referred also to human rights law and limitations recognized by the European Court of Human Rights for conduct of medical professionals. Dr Behrens further strengthened his arguments by examining laws from jurisdictions that have acted against conversion practices or are planning laws on this matter, including the Australian Capital Territory, Canada, France, Germany, Malta, New Zealand, Queensland, Spain, Victoria and Scotland.

By submitting his amicus brief, Dr Behrens joined other prominent amici who filed observations. These included the American Psychological Association, 20 US Senators, 167 Members of the US Congress, and 21 US States that have prohibited or restricted conversion practices.

Dr Behrens said: “It was an honour to address the US Supreme Court on this important matter. Where conversion practices are concerned, it is important to keep in mind whose rights had been violated in the first place. The children and young people who were subjected to these methods never sought to interfere with the rights of others, they just wanted to be who they are. The protection of this freedom is a duty for every State, and Colorado merely acted in fulfilment of that duty.

“My particular thanks go to Sonia Miller-Van Oort, Alexander Beeby, Abigail Denne and the entire team at Sapientia Law Group for their editorial work and for submitting the brief, as counsel of record, on my behalf.”

Dr Behrens' amicus curiae brief is available here.