The United States uses economic sanctions more than any other power, and American policy makers cite human rights issues as the most frequent justification of sanctions. International human rights standards, embodied in a range of treaties and institutions, commit countries to observe a wide gamut of rights and freedoms. We investigate whether, when and how U.S. sanctions help this emerging human rights regime. Ideally, sanctions would hold violators responsible, and would increase the cost of human rights abuses. We develop a theoretical argument that distinguishes the incentives and capacity of Congress and the Presidency to sanction human rights violations. We argue that agreement between the branches with an international human right standard is important in setting up the type of enforcement that is optimal for target compliance. We also argue that international treaties make a difference, even absent such agreement. We use a new database of U.S. economic sanctions to show that the U.S. has been enforcing international human rights standards in a manner that is perhaps surprisingly robust.