See http://www.scotusblog.com/case-files/cases/murr-v-wisconsin/
This decision is certainly one for property law casebooks, and it provides a new test that will now play a major role in regulatory-takings litigation. It’s not clear, however, that the stakes are quite as high as the opinions suggest. The denominator question, after all, is just a preliminary step; courts must then decide whether a taking occurred, applying (as relevant here) the tests from Penn Central Transportation Co. v. New York City or Lucas v. South Carolina Coastal Council. In some cases — like this one — judges may be able to agree on whether a taking has occurred despite disagreement on what constitutes the denominator. Moreover, the Penn Central test, the usual test in regulatory-takings cases, is famous for the broad discretion it affords courts. Whether the denominator test preferred by the dissent and the Murrs would actually have spurred courts to find more takings, despite their broad discretion at the second step of the process, is an interesting but unclear empirical question. The more certain result of Murr is that the takings analysis is now more complex. Courts and litigators will spend the coming years interpreting the Supreme Court’s new, open-textured definition of the takings denominator. http://www.scotusblog.com/2017/06/opinion-analysis-regulatory-takings-case-court-announces-new-test/
