The path to Arizona's proposed law that would allow businesses to refuse service to gays and lesbians begins over twenty years ago in Oregon and winds through a photographer's studio in New Mexico.
Two Native American men who worked at an Oregon drug rehab center were fired two decades ago for smoking peyote -- an illegal drug -- at a church service. They sued, claiming an exemption from the state's drug law, arguing that their use of peyote was part of a tribal religious ritual.
But they lost in the U.S. Supreme Court, which ruled in 1990 that religious groups were not exempt from general laws that apply to everyone.
An outraged Congress responded in 1993 by passing the "Religious Freedom Restoration Act," barring the government from imposing a "substantial burden" on a person's exercise of religion, even if the burden results from a general law that's not aimed at a religious group or practice.
The Supreme Court later limited the reach of the act, prompting many states, including Arizona, to pass versions of their own.
The proposed bill under fire in Arizona would amend that state's version of the Religious Freedom Restoration Act, which provides that "government shall not substantially burden a person's exercise of religion even if the burden results from a rule of general applicability."
Last year, advocates of the Arizona’s religious-freedom laws were alarmed by a court decision in the neighboring state of New Mexico against the owners of an Albuquerque photo business that refused to photograph the commitment ceremony of two women.
New Mexico's Supreme Court ruled in August that "a commercial photography business that offers its services to the public, thereby increasing its visibility to potential clients," is subject to state anti-discrimination laws "and must serve same-sex couples on the same basis that it serves opposite-sex couples."
Supporters of the proposed Arizona law considered that ruling a call to action: "This is not what the founders of this nation had in mind when they drafted the First Amendment," said a set of talking points circulated by the bill's supporters.
The existing Arizona religious freedom law applies to "a person's exercise of religion." The proposed new law would expand that protection to include businesses and would allow them to cite a violation of their religious beliefs as a defense if they're sued for failing to provide service.
"This new law says whoever you are and however you operate in the public sphere, you can pick and choose who you want to serve, regardless of non-discrimination law. It's essentially the Wild West. Anything goes," said Kate Kendell of the National Center for Lesbian Rights.
Such a law, she says would be invalid under the U.S. Constitution. "It's a flat out violation of well-established protections against discrimination based on race and gender."
But because the Supreme Court has never said whether the Constitution prohibits discrimination on the basis of sexual orientation, gay rights groups believe the proposed Arizona law would make it difficult for gays and lesbians to prevail against Arizona business owners who cited religious beliefs for refusing to serve them.
And Arizona's own public accommodation law, while barring discrimination on the basis of race or sex, says nothing about prohibiting actions based on sexual orientation, either.
Meanwhile, the idea that a business can claim religious freedom to opt-out from the law of the land has divided the federal courts on another subject: The requirement that employers pay for their employee's contraceptive coverage under Obamacare.
Two family-owned companies are citing the federal Religious Freedom Restoration Act in claiming that paying for the coverage would violate their religious beliefs.
The U.S. Supreme Court takes up that issue next month.