The Recognition Theory of Rights, Customary International Law and Human Rights David Boucher Cardiff University This article addresses the most fundamental question in the philosophy of rights. If there are any moral rights, where do they come from and how do we acquire them?The difficulty of answering the question is compounded when asked in relation to universal rights and obligations where the international community in which they function is far less solidarist than at the domestic level. The suggestion is that while answers that presuppose something about the ontology of the person, such as an emphasis on basic needs, or inherent human dignity, are prevalent, they are a convenient fiction. It is contended that the rights recognition thesis, typically associated with British Idealism, is best exemplified with reference to common law theory,and customary international law,and provides a far more adequate account of what it means to have universal rights and obligations. It is suggested that customary international law functions in a similar way to how natural law used to function. The article concludes by emphasising the importance of customary international law in articulating the universal obligations of states and holding them to account for their actions. It addresses the question of what it means to have a universal right, and not what universal rights it is desirable to have. Keywords: rights recognition; British Idealism; customary international law; human rights; international justice It is widely acknowledged, sometimes approvingly, that international law and human rights law are fundamentally based upon and are codifications of customary international law (Perreau-Saussine, in Perreau-Saussine and Murphy, 2007, p. 228). 1 It has been convenient in the absence of an international legislative authority to try to establish that the practices of states conform to certain moral rules which are implicitly and explicitly acknowledged as binding. The establishment of which rules are genuinely universally binding is a discursive activity evidentially based on the actual practices of states, legal precedent and the opinions of learned jurisprudents. Customary international law is the foundation of the modern law of nations, but it is true to say that in the last 40 years or so it has gradually been replaced by treaties as the primary source of international law,many of which explicitly or implicitly codify customary law, or extend it. The International Law Commission has accelerated this process by its continuing efforts purposely to codify customary interna- tional law. The advantage is that treaty law is able to specify definite and precise rules of law. It is nevertheless important not to lose sight of the fact that where a treaty and customary international law coincide in their content, should the treaty cease to exist, for whatever reason, the customary law remains binding (Dixon, 2005, p. 24, p. 35). It may indeed be preferable, easier to police and enforce and hence more effective, when human rights are doi: 10.1111/j.1467-9248.2011.00890.x POLITICAL STUDIES: 2011 VOL 59, 753–771 © 2011 The Author. Political Studies © 2011 Political Studies Association