This is the second post of a two-part set. Click to read Part I.

As I noted in a previous post, the pending case of United States v. DTE Energy, Inc. tacitly raises issues concerning the constitutionality of both Supplemental Environmental Projects (SEPs) and the citizen suit provisions of environmental laws. This second post considers another constitutional issue that may emerge in the DTE Energy litigation: whether SEP agreements – and citizen suits more generally – interfere with a “core executive function” of the president and executive branch and longstanding constitutional notions of separation of powers. To resolve that question soundly, one must look to the text of the Constitution itself, the Federalist Papers, and the relevant body of law that the lower federal courts have already developed.

Notably, neither the Constitution nor the Federalist Papers provide a clear indication of what constitutes a “core executive function” or the extent to which federal law enforcement activities may be delegated. Nonetheless, there are numerous historical precedents for delegations of law enforcement responsibilities to private parties – some of which go well back into English law – and none of these prosecutorial arrangements have been successfully challenged in the courts.

As far back as the 14th …