The Establishment Clause in the First Amendment to the United States Constitution provides that “Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof.” In applying the Establishment Clause to disputes ranging from prayer in schools and in state legislatures to monuments displaying the Ten Commandments or crosses on public grounds, the U.S. Supreme Court has acknowledged the strong role played by religion and religious traditions throughout our Nation's history—while recognizing that governmental intervention in religious matters can itself endanger religious freedom.

The Supreme Court described this balancing act: “Our institutions presuppose a Supreme Being, yet these institutions must not press religious observances upon their citizens. One face looks to the past in acknowledgment of our Nation's heritage, while the other looks to the present in demanding a separation between church and state. Reconciling these two faces requires that we neither abdicate our responsibility to maintain a division between church and state nor evince a hostility to religion by disabling the government from in some ways recognizing our religious heritage.”

In South Dakota, as in all states, the Establishment Clause of the First Amendment to the U.S. Constitution is the guiding principle for matters involving the separation of church and state. This clause prevents the government from making laws that establish an official religion or prefer one religion over another, while also prohibiting the government from interfering with an individual's freedom to practice their religion. The U.S. Supreme Court has interpreted this clause through various rulings, establishing a complex jurisprudence that seeks to balance respect for religious traditions with the imperative to maintain a secular government. This balance is reflected in decisions regarding religious displays on public property and prayer in public schools, where the Court has often used tests such as the 'Lemon test' (from Lemon v. Kurtzman) to determine whether a government action is permissible. The test includes criteria such as whether the action has a secular purpose, whether it advances or inhibits religion, and whether it fosters an excessive government entanglement with religion. In South Dakota, state statutes and practices must align with these constitutional principles and relevant Supreme Court decisions, ensuring that while religious heritage may be acknowledged, government actions do not promote or affiliate with any particular faith.