The First Amendment provides, “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof. …” The two clauses of this sentence, commonly referred to as the Establishment Clause and the Free Exercise Clause, ostensibly divide the constitutional principle of religious freedom into two doctrinal realms, each with its own particular principles and methods. Stated very generally, the Establishment Clause precludes the government from favoring any particular religion or group of religions, or from preferring religion over nonreligion (though the scope of this limitation is evolving rapidly), while the Free Exercise Clause limits the government’s authority to interfere with religious beliefs and practices. Taken together, both Clauses are designed to promote religious freedom by limiting the capacity of the government to become excessively involved in religious matters. Both Clauses apply to the states through the Fourteenth Amendment.
As a preliminary matter, although “religion” is the protected subject under both the Establishment Clause and the Free Exercise Clause, the Court has never defined religion in a constitutional context. Typically, a court will accept any nonfrivolous claim that a particular set of beliefs constitutes a religion. Certainly the term “religion” includes all organized systems of faith premised on either a supreme being or some similar transcendent authority. This is true regardless of how bizarre the belief system or how recent the heritage of that system. In a sense, religion is in the heart of the believer. Thus, although a court may inquire into the sincerity of one’s religious beliefs, a court will not inquire into the legitimacy or believability of those beliefs. While the Court has stated that merely philosophic or personal beliefs do not qualify as a religion, the difference between a philosophy and a religion is far from clear, and the Court has never applied this distinction. Presumably, therefore, something like existentialism is not a religion, although one could certainly make a case to the contrary.
In what follows, we examine the various doctrines the Court has developed under the religion clauses, focusing first on the Establishment Clause and then on the Free Exercise Clause. We will also note significant areas in which the clauses seem to overlap. The primary difficulty the student will confront in this area derives from the Court’s inability to settle on a relatively consistent interpretation of the religion clauses. As a consequence of this recurring instability, religion clause cases cannot be reduced to a simple formula, but must be examined from a variety of jurisprudential perspectives.
The Establishment Clause provides, “Congress shall make no law respecting an establishment of religion.” These words have been interpreted as limiting governmental action of two types:
The various subdivisions of these general categories will be discussed below. At this point, it is important to note, however, that the scope and content of the second category are the subjects of sharp debate on the Court. At the heart of that debate are two competing interpretations of the Establishment Clause—separationism and nonpreferentialism. That debate is further complicated by a number of compromise approaches that borrow from each of these interpretive theories. While a student need not become immersed in theory to understand the Court’s Establishment Clause jurisprudence, some familiarity with these particular theories and their variations will provide a more thorough appreciation of that jurisprudence. A brief overview follows.