J.B. Ruhl

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Environmental Law

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The substantive contours of the Endangered Species Act (ESA) have been largely worked out for quite some time. Starting in the mid-1990s, however, opponents of Fish and Wildlife Service and National Marine Fisheries Service decisions realized that the methodological contours of the ESA were not nearly as settled as their substantive kin. Industry and environmental interests alike appreciate that how these methodological rules get worked out could revolutionize the ESA for decades to come, and during the 1990s they opened the debate over ESA methodology and have been going strong at it ever since. This Article explores the breadth and depth of the ensuing battle over ESA methodology. It begins by laying out a framework for evaluating decisionmaking methodologies. One basis on which we might choose how to go about making decisions is what level of confidence we wish decisions to enjoy. Also, how we frame the hypotheses to be tested will influence who favors which methodology. And methodology selection also has much to do with aversion to mistaken conclusions about whether the hypothesis is true.

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