Inequality in the creation of environmental harm: looking for answers from within

To date, many environmental policy discussions consider inequalities between groups (typically by comparing the average or aggregate resource use of one group to another group), but most ignore disproportionalities within groups. Disproportionality, as discussed in a small but growing body of work, refers to resource use that is highly unequal among members of the same group, and is characterized by a positively skewed distribution, where a small number of resource users create far more environmental harm than “typical” group members. Focusing on aggregated or average impacts effectively treats all members of a group as interchangeable, missing the few “outliers” that actually tend to be responsible for a large fraction of overall resource use. This chapter offers reasons why we should or should not expect disproportional production of environmental impacts (from both mathematical and sociological perspectives), looks at empirical evidence of disproportionality, and offers a framework for detecting disproportionality and assessing just how much difference the outliers make. I find that in cases where the within-group distribution of resource use is highly disproportionate (characterized by extreme outliers), targeting reduction efforts at the disproportionate polluters can offer opportunities to decrease environmental degradation substantially, at a relatively low cost.