Law versus Norms: The Impact of Human-Rights Treaties on National Bills of Rights

The constitutional incorporation of international human-rights law is often seen as one of the most powerful ways in which treaty norms can be enforced at the local level. This paper examines empirically if and how human-rights treaties alter rights commitments in national constitutions. Analyzing the adoption of 103 constitutional rights – only some of which are enshrined in treaties – in 188 countries over a sixty-one-year period, the paper finds that the impact of human-rights treaties on a country's menu of constitutional rights is limited. In some cases, treaty ratification even results in the adoption of fewer constitutional rights.