The federal statutes that require government to justify any substantial burden on religious exercise by a compelling interest pursued in the least restrictive way - stronger than the constitutional rule, and the basis of most modern religious-liberty claims by prisoners, congregations and employers.
The First Amendment's Free Exercise Clause, as the Supreme Court has read it since 1990, does not excuse a person from a neutral law of general application merely because it burdens their religion: a generally applicable rule that happens to forbid a religious practice is constitutional without any special justification. Congress responded with the Religious Freedom Restoration Act, which restores the older test as a matter of statute: the federal government may not substantially burden a person's exercise of religion, even by a neutral rule, unless it demonstrates that the burden furthers a compelling governmental interest and is the least restrictive means of doing so. The Court held that RFRA could not be applied to the states, so Congress passed the Religious Land Use and Institutionalized Persons Act, which imposes the same test on state and local governments in two areas where Congress has authority: land-use regulation affecting religious assemblies, and the treatment of people confined in prisons, jails and other institutions. Many states have enacted their own RFRAs covering state action generally.
The test has teeth. Under RLUIPA prisoners have won the right to keep a beard, wear religious headwear, receive a religious diet and hold group worship where the institution could not show a genuine security need that a narrower rule could not meet; congregations have defeated zoning denials that treated churches worse than comparable secular assemblies. Under RFRA, closely held corporations have been exempted from a federal contraceptive-coverage mandate, and a claimant may recover damages against federal officials in their individual capacity. The claimant must show a sincere religious belief and a substantial burden on it - a cost, penalty or denial of a benefit for acting on the belief - but courts do not judge whether the belief is central, reasonable or correct.
The constitutional claim has also revived. Where a law is not truly neutral or generally applicable - where it makes exceptions for secular reasons but not religious ones, or was adopted with hostility to a religion - the compelling-interest test applies directly under the Free Exercise Clause, and the Court has applied that principle to pandemic gathering limits and to a city's refusal to work with a religious foster-care agency. Which of the three routes - the Constitution, RFRA, or RLUIPA and its state counterparts - is available depends on who the defendant is and what it did.
The first question a lawyer asks is who is burdening the practice - a federal agency, a state or local government, a prison, a private employer - because that decides which statute applies and whether any does; a private employer, for instance, is reached by Title VII's religious-accommodation duty rather than by RFRA. The second is the record: a written request for the accommodation and the written refusal or the rule relied on. Several national organisations litigate these claims at no cost to the claimant, and a lawyer can tell you whether your situation is one they take.
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