To make international human rights enforceable on the ground, they must be localized. In the process, domestic stakeholders may attempt to contest or reshape the rights. Although norm localization has received much scholarly attention, prior publications have failed to explain which elements of a human rights treaty might be contested and why. Based on signaling theory, this article starts from the assumption that governments’ commitments to human rights treaties raise corresponding expectations on the part of other states. Consequently, contestation is relatively more likely when a government considers the audience costs for backtracking on its commitments to be lower. The article goes on to suggest that expected audience costs vary for different treaty elements—primary, secondary, and tertiary—which in turn affects the relative likelihood of contestation. The article develops a novel approach to norm localization and applies it to the making of a treaty-transposing law against torture and enforced disappearance in Thailand. The case study largely confirms the model but also demonstrates the significance of local specifics, such as a history of impunity. The findings allow theoretical and practical conclusions for the legislative localization of international human rights law.