Allocating emissions rights: Are equal shares, fair shares?
In a world where greenhouse gas emissions must be reduced, what is the fair way to allocate rights to the limited available emissions? For many, the answer is that a fair allocation is an equal per capita allocation. From at least as far back as 1988, it has been proposed that emissions rights be allocated between nations on an equal per capita basis. That is to say, it has been proposed that nations move to a situation where the quantity of emissions rights allocated to a nation in a given year is calculated by dividing the rights to the permitted global emissions for that year by the global population in that year (or an agreed base year) and then multiplying the quotient by the nation’s population in that year (or the agreed base year). This is the approach advocated by the well-known Contraction and Convergence proposal. And from at least as far back as 1991, it has been proposed that emissions rights be allocated on an equal per capita basis within nations. That is to say, it has been proposed that the rights to a nation’s permitted emissions in a given year should be allocated equally to all adult individuals within that nation. Various emissions trading schemes which allocate rights in this manner have since been proposed and these so-called personal carbon trading schemes are currently the focus of considerable interest within the UK.
But how might one explore whether an equal per capita allocation (henceforth, EPCA) is, in fact, fair? One approach is to see whether support for such an allocation exists within the literature on distributive justice, that branch of the philosophical literature concerned to provide a specification and justification of what constitutes a fair distribution of resources within society. However, Stephen Gardiner notes that “Very few moral philosophers have written on climate change” and that most writings on the moral dimensions of climate change have instead come from “non-philosophers”. Inevitably, non-philosophers have limited familiarity with the philosophical literature on justice, and as it is mainly non-philosophers who have advocated EPCA, it is therefore not surprising that their arguments tend not to draw upon this literature. This paper sets out the main argument that non-philosophers make for EPCA, namely that the atmosphere or sinks for greenhouse gases are a commons. The paper then proceeds to examine whether there is anything within the justice literature that supports such an argument or that provides alternative justifications for EPCA. However, justice remains a contested concept, David Miller summarizing the current situation as being “one of…fairly radical disagreement as to which theory of justice is actually correct”. And in recognition of the contested nature of the concept, the paper surveys three leading approaches to justice, right-libertarianism, egalitarian liberalism and left-libertarianism, to determine the level of support that exists within each for EPCA.
The paper finds that there is little support within the literature for the notion that the atmosphere or emissions sinks are a commons, at least in the (implicit) sense that non-philosophers use the word. It further finds that there is no alternative support for EPCA from within right-libertarianism. Support from egalitarian liberalism and left-libertarianism is at best qualified in the sense that an equal per capita allocation may be the closest allocation in practice to the somewhat unequal allocations that these perspectives would find fairest in theory.