The protections afforded citizens in human rights treaties drafted by international organisations such as the United Nations may frequently be seen as a way of protecting unpopular minorities such as offenders from the “tyranny of the majority”.Yet, criminal justice policies promulgated by these same bodies can often cut, swordlike, deep into citizens’ freedoms. This tension – between drives towards human rights, on the one hand, and towards criminalisation and punitive measures on the other –is particularly acute in the field of counterterrorism, where bodies such as the UN Security Council have been active since the events of 9/11. Taking the field of counterterrorism as an exemplar, it is the aim of this paper to explore the tension between the “shield” and “sword” functions of international organisations, drawing on two case studies. The first concerns the United Nations where the security of the state has secured a major advantage over the ethic of human rights, within rather than in conflict with the UN framework of international oversight. The second examines the European Union, where the enactment of a significant body of counterterrorism legislation since 9/11 has driven radical and permanent change with significant implications for human rights.