Whenever legislators and regulators adopt a regulatory change, they face an important question: how should existing actors be required to respond to the new law? For example, if regulators drastically reduce the level of emissions that new plants are permitted to discharge, they might...

While one primary goal of the Endangered Species Act is to prevent the global extinction of species, it is less clear whether the Act is intended, and can be used, to protect species that are endangered solely within the United States. Although the global preservation of species may be...