Allies in the streets and illiberal in the sheets? Women in the dating market punish gender incongruent sexual behaviour more than men.

Traditionally, heterosexual women in modern, liberal democracies have constituted a core constituent ally for the defence of LGBTQ+ rights and the inclusion of individuals with diverse sexual and/or gender identities. In this paper, we argue that the increased tolerance towards sexually diverse individuals among women does not translate beyond diffuse support and individual-level behaviour when it comes to women’s own preferences regarding their potential partners. Theoretically, we maintain that heterosexual women penalise potential partners that have engaged in gender-incongruent sexual activity in the past whereas men do not. Relying on a unique, pre-registered visual conjoint experiment from the UK and Spain, we demonstrate that heterosexual women are far more likely to reject potential partners that have engaged in any same-sex sexual activity via-a-vis heterosexual men. In essence, bi men are systematically penalised whereas bi women are not. This asymmetry in heterosexuals’ tolerance of gender-incongruent sexual behaviour results in an imbalance in the supply-and-demand equilibrium between men and women which may contribute to explaining the imbalances between bi-identifying men and bi-identifying women.