Congress passed the Endangered Species Act (ESA) in 1973 to protect species at risk of extinction. The federal government claims the Constitution’s Commerce Clause, which gives the federal government the power to regulate economic activity between states, also grants it authority to regulate endangered and threatened species nationwide. Under the ESA, the federal government imposes regulations on property owners to protect species that live in a single state (i.e., intrastate), even when protected species have little to no impact on interstate commerce.