Davis involved an Idaho territorial statute directed at POLYGAMY. The law required voters to foreswear membership in any organization that "teaches, advocates, counsels or encourages" its members to undertake polygamous relationships. Davis was convicted of swearing falsely.
Justice STEPHEN J. FIELD, speaking for the Supreme Court, saw the case as identical to REYNOLDS V. UNITED STATES (1879). The free exercise clause of the FIRST AMENDMENT protected religious beliefs not acts that prejudiced the health, safety, or good order of society as defined by the legislature operating under its POLICE POWER. Field concluded that if something is a crime, then to teach, advise, or counsel it cannot be protected by evoking religious tenets.
The decision became one of the principal underpinnings of what later came to be called the "secular regulation"...