Abstract: In the last few years, many countries have introduced (or are proposing to introduce) legislation on ‘conversion therapy’, prohibiting attempts to change or suppress sexual orientation and/or gender identity. This legislation covers ‘aversion therapy’, a form of torture that has already been criminalized in most progressive countries, and ‘talk therapy’, involving things like counselling, psychoanalysis, and prayer. Puzzlingly, when an evidence base is pointed at to justify claims that such attempts are ineffective and harmful, the evidence is almost exclusively about sexual orientation, and not gender identity. So why have the two been paired in conversion therapy legislation? I consider the scientific basis for the claim that gender identity is innate in the same way that (it is believed that) sexual orientation is, and, if there’s time, some philosophical and political arguments for the pairing. I argue that both the evidence base and the arguments are insufficient to justify the pairing. The implication is that conversion therapy legislation should be about sexual orientation alone, and activists for lesbian, gay and bisexual rights should be vigilant about academic and political work that simply rolls the two together. Holly Lawford-Smith is an Associate Professor in Political Philosophy at the University of Melbourne. Her last book, Gender-Critical Feminism, was published with Oxford University Press in 2022, and her next book, with the same publisher, is expected in July this year. She teaches across a range of areas in moral and political philosophy and social metaphysics, and her research at the moment is focused on issues in radical and gender-critical feminism.