May a religious Christian baker refuse to bake a wedding cake for a same-sex couple? That is the issue the Supreme Court will be considering on Tuesday. To begin with, it’s important to recognize that this issue arises only when there is an applicable law that prohibits businesses from discriminating against gays or lesbians. In many parts of the country, no such law exists, so bakers are free to discriminate against gay and lesbian customers, regardless of whether they’re looking for a wedding cake, a birthday cake, or a loaf of bread. Of course, the Supreme Court held in 2015 that the Constitution requires every state to allow same-sex couples to marry. But the Constitution only restrains only government actors, not private ones. Without laws forbidding discrimination by employers, landlords, and businesses, a gay man could get married on Sunday, then be legally fired from work on Monday, booted out of his apartment on Tuesday, and denied service at a restaurant on Wednesday. The baker in the case before the Supreme Court, Jack Phillips, lives in Colorado, which does have a state law that prohibits businesses from discriminating based on sexual orientation. After a same-sex couple complained to the Colorado Civil Rights Commission that Phillips had refused their request for a wedding cake, the commission ordered Phillips to make wedding cakes either for all couples or no couples. You might think that this case is primarily about the baker’s religious liberty. After all, the First Amendment provides that government shall make no law “prohibiting the free exercise” of religion. But in a 1990 decision by conservative Justice Antonin Scalia, the Supreme Court held that religious objectors have no constitutional right to be exempted from generally applicable laws that are not targeted at religious practice. In other words, a law forbidding the use of peyote for religious rituals would be unconstitutional. But a general law forbidding the use of peyote by everyone is constitutional, even if it prevents Native Americans from using peyote for religious purposes. Since the Colorado nondiscrimination law applies to businesses generally and is not targeted at