Free Exercise Clause of the First Amendment

The Free Exercise Clause is the accompanying clause with the Establishment Clause of the First Amendment to the United States Constitution. The Establishment Clause and the Free Exercise Clause together read:

In 1878, the Supreme Court was first called to interpret the extent of the Free Exercise Clause in Reynolds v. United States, as related to the prosecution of polygamy under federal law. The Supreme Court upheld Reynolds' conviction for bigamy, deciding that to do otherwise would provide constitutional protection for a gamut of religious beliefs, including those as extreme as human sacrifice. The Court said: "Congress cannot pass a law for the government of the Territory which shall prohibit the free exercise of religion. The first amendment to the Constitution expressly forbids such legislation." Of federal territorial laws, the Court said: "Laws are made for the government of actions, and while they cannot interfere with mere religious beliefs and opinions, they may with practices."

Jehovah's Witnesses were often the target of such restriction. Several cases involving the Witnesses gave the Court the opportunity to rule on the application of the Free Exercise Clause. Subsequently, the Warren Court adopted an expansive view of the clause, the "compelling interest" doctrine (whereby a state must show a compelling interest in restricting religion-related activities), but later decisions have reduced the scope of this interpretation.

The history of the Supreme Court's interpretation of the Free Exercise Clause follows a broad arc, beginning with approximately 100 years of little attention, then taking on a relatively narrow view of the governmental restrictions required under the clause, growing into a much broader view in the 1960s, and later again receding.

The first case to closely examine the scope of the Free Exercise Clause was Reynolds v. United States in 1878. A case dealing with the prosecution of a polygamist under federal law, and the defendant's claim of protection under the Free Exercise Clause, the Court sustained the law and the government's prosecution. The Court read the Free Exercise Clause as protecting religious practices, but that didn't protect Reynolds' practices which were crimes. This case, which also revived Thomas Jefferson's statement regarding the "wall of separation" between church and state, introduced the position that although religious exercise is generally protected under the First Amendment, this does not prevent the government from passing neutral laws that incidentally impact certain religious practices.

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