There are slaves living today in the West African Republic of Niger and their plight is being exacerbated by that country’s aggressive program of legal westernization. Under the guidance of the United States and other Western countries, Niger recently passed a surfeit of new laws, including some that introduce and enforce the notion of private property ownership. The theory – widely accepted by donor countries and international development experts – is that uniform, easily enforceable rights in private property will spur investment and help breathe life into Niger’s moribund economy. This paper does not dispute the validity of that legal and economic theory, but it shows that the introduction of the legal concept of private property has resulted in unintended, potentially devastating consequences for Niger’s contemporary slaves, a result that is particularly ironic given that some of those laws were intended to abolish slavery. Drawing upon insights from the language and culture of the Zarma people of Niger, and upon careful ethnographic fieldwork among slaves, the paper explains how legal westernization has gone awry, and suggests a new, culturally attuned approach to law reform in Niger and across the developing world.