The U.S. Environmental Protection Agency’s (EPA’s) enforcement program has long been the backbone of environmental enforcement in the United States. That program may now be bound for dramatic change. This Article analyzes the threats posed to the Agency’s program by the U.S. Supreme Court’s forthcoming decision in Securities and Exchange Commission v. Jarkesy, in which three constitutional questions presented cut to the core of administrative enforcement.

Supplemental environmental projects (SEPs) have received a growing amount of attention in recent years, from the Donald Trump Administration banning their use in settlements, to regulation and guidance from the Joseph Biden Administration reversing the ban, to legislative proposals prohibiting them altogether. This Article examines SEPs’ legality under existing law, focusing on claims that they violate the Miscellaneous Receipts Act and the Antideficiency Act. It begins with a brief history of SEPs’ policy evolution and the limitations on the U.S. Environmental Protection Agency’s and U.S.