When the Natural World Presents Facts to Political Theorists

An Exchange of Views The recent article by Marco Verweij in Law and Society Review1 offers a promising approach for studying the effectiveness of rules for achieving environmental goals. He suggests treating levels of toxic substances as the independent variable, and then looking at that variable across a range of legal and regulatory cultures. In the article, he argued that the adversarial culture of the United States compared to the cooperative culture in civil law nations meant that firms in Europe were more proactive in cleaning up their emissions than was the case in the United States. To make this point, he sought to compare chemical pollution in the Rhine to that found in the Great Lakes of North America. He also claimed that the International Joint Commission (IJC), a small-but-respected international organization, had worsened the situation in the Great Lakes. Verweij's approach is so promising, but the execution so flawed, that a comment on his thoughtful effort seemed in order. My comments will address, first, the scientific/technical difficulties in his study and, then, political/social science issues. It concludes with a brief review of other ways we could test his idea. I believe correcting the flaws related to the biophysical science and executing a relevant study along the lines he suggests would advance our understanding of how differences in legal cultures and institutions produce realworld outcomes. Lakes Are Not Rivers and Other Biophysical Issues Verweij claims he has used a most similar system design. He notes that all the nations in his study are industrial democracies and that the only relevant difference lies in their legal cultures (civil versus common law). In one utterly crucial respect, however, which he acknowledges but dismisses, he has chosen a most different system design: Lakes do not behave like rivers. Because toxics are central to his argument, this error matters. Studies of this nature must make sure that similar cases really are similar-- politically and ecologically. Verweij assumes that chemicals found in a sample of water from the Great Lakes or at the outlet of the river Rhine reflect the success or failure of reduction of toxic substance releases by industry. This is unlikely. Dr. Sarah Green, an environmental chemist, explains the difference like this: In simplest terms, the accumulation (or loss) of a chemical in a lake results from differences in the input and removal (by volatilization or degradation) during the residence time of water in the lake (170 years for Lake Superior). The amount actually measured in the water depends on what fraction of the total has sorbed to the sediment. In a river, measurements of water at the mouth indicate (1) the amount put in during the travel of water downstream (a few weeks for the Rhine) and (2) leaching of material that was historically sorbed to the sediments.2 Thus, his claim on p. 1016 is in error. "It is unlikely that the Great Lakes firms made greater strides in reducing lake pollution [between 1970 and 1988] than the Rhine companies . . . for if they had diminished their pollution by more than 80% to 90% . .. they would have virtually eliminated the chemical pollution of the lakes by the end of the 1980s." Even if Verweij ignores legacy chemical pollution in or from Lakes Superior, Michigan, and Huron, he would still have to cope with the 2.6 years average retention in Lake Erie and the 6-year retention in Lake Ontario, both of which allow chemicals to concentrate as processes of suspension, settlement, and resuspension take place. On top of all this, the vast surface area of the Great Lakes means that airborne deposition of chemicals from outside the Great Lakes basin also cause pollution; indeed, for some species of chemicals airborne depositions is the primary source of inputs. For example, all the compounds he lists in Table 1 come into the Great Lakes primarily from the atmosphere, except for the sedimentary sources of PCBs. …