The Supreme Court has had many occasions in recent years to consider what it calls "the constitutional principle of separation of powers." The principle in question has been effusively praised and on occasion vigorously enforced. But just what is it? The Court clearly believes that the Constitution contains an organizing principle that is more than the sum of the specific clauses that govern relations among the branches. Yet notwithstanding the many testimonials to the importance of the principle, its content remains remarkably elusive.
The central problem, as many have observed, is that the Court has employed two very different conceptions of separation of powers in recent years. On the one hand, there is the "formal" understanding, emphasizing that "[t]he Constitution sought to divide the delegated powers of the new Federal government into three defined categories, Legislative, Executive, and Judicial, to assure, as nearly as possible, that each branch of government would confine itself to its assigned responsibility." On the other hand, there is the "functional" understanding, stressing that the three branches do not "operate with absolute independence," and that the Constitution requires only that "the proper balance between the coordinate branches" be maintained. The Court has alternated between the formal and the functional constructions, with a swing group of Justices evidently happy to embrace one or the other as suits the needs of the moment.
When we step back from the doctrinal inconstancy and examine the outcomes of the Court's recent separation-of-powers decisions, however, a readily discernible pattern emerges. The formal theory is regularly used in evaluating (and invalidating) attempts by Congress to exercise governmental power by means other than the enactment of-legislation; the more elastic functional approach is favored in reviewing (and approving) duly-enacted legislation that regulates or reallocates the functions performed by the other two branches. Unfortunately, this pattern does not follow from the tenets of either formalism or functionalism. Applied consistently, formalism would impose strict limitations on efforts to scramble executive and judicial functions,10 and functionalism would probably lead the Court to uphold at least some of the extra-legislative congressional controls that have been disapproved. All of which suggests that neither formalism nor functionalism provides a satisfactory account of the constitutional principle of separation of powers – at least as it operates in practice.
Thomas W. Merrill,
The Constitutional Principle of Separation of Powers,
Sup. Ct. Rev.
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