Religious Liberty and State Constitutions
The fact is sometimes overlooked that the state constitutions, some of which were written written before the federal Constitution, include explicit protections of religious liberty and church-state separation, some even more comprehensive and specific in their guarantees and prohibitions than the U.S. Constitution. All of the state constitutions deal with religious freedom and all support the church-state separation principle. Forty-six states explicitly protect freedom of worship or conscience, while thirty-five states prohibit establishment of any state religion.
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Church and State