Late last year, the U.S. District Court for the District of Utah rendered a groundbreaking decision in People for the Ethical Treatment of Property Owners (PETPO) v. United States Fish & Wildlife Service, 2014 WL 5743294 (D. Utah Nov. 4, 2014). The court held that federal regulation of the Utah prairie dog—a threatened species found solely in southwestern Utah—under the Endangered Species Act (ESA) exceeded the federal government’s authority under the Commerce and Necessary and Proper Clauses of the U.S. Constitution. The decision was the first from any court to invalidate federal regulation of a purely intrastate species on federalism grounds. The service, as well as the environmental intervenor Friends of Animals (FOA), has appealed the decision to the Tenth Circuit Court of Appeals. Given the stakes, the PETPO case stands a good chance of landing in the U.S. Supreme Court.