Re: Indiana's 'No Gay Wedding' Pizzeria Has Closed
Yeah, that's the private/difference. A private club or individual has a lot more leeway. Businesses which operate in the public space don't that freedom.
For constitutional purposes, people and the businesses they run are both private persons. Almost nothing in the Constitution applies to private persons--including discrimination by those persons. The Thirteenth Amendment was relied on in one case, Jones v. Alfred Mayer (upholding law against race discrimination in sale of housing as exercise of Congress's power to prohibit private persons from imposing "badges and incidents" of slavery); the Fifteen Amendment has been used in several cases where private persons interfered with voting; and the Commerce Clause was used as Congress's authority for prohibiting discrimination in public accommodations in the Civil Rights Act of 1964.
You're right that private clubs have more freedom not to serve people. But often the reason has not been that they were not serving the general public, but rather that no
government discrimination was involved. A good example is Moose Lodge No. 107 v. Irvis. The lodge in Irvis, citing its membership rules, had refused to serve the black guest of a white member at either its bar or its restaurant. He sued, but he lost. The Supreme Court held the fact the state had issued the lodge a liquor license and the fact it used public utilities were not enough to convert its race discrimination into the
state action required for the Fourteenth Amendment to apply.
Discrimination in public accommodations on the basis of sexual orientation is not prohibited by federal law. Where states have made sexual orientation a prohibited basis for discrimination in public accommodations, they have relied on their inherent authority to make laws and policies concerning public health, safety, and welfare. It's generally true that the more commercial the character of a thing the state law defines as a public accommodation, the more likely that a state can prohibit discrimination without running afoul of the freedom of association. See Roberts v. Jaycees for a good discussion of this.
The hotel that rents rooms to the guests at a same-sex wedding, the limousine service that transports them, and the caterer who supplies the food probably would not have very strong First Amendment arguments for refusing to do these things, assuming they met the definition of public accommodations under the state's law and that law prohibited them from discriminating on the basis of sexual orientation. And yet the fact a public accommodation is mainly engaged in commerce does not automatically mean a state law can prohibit it from discriminating against homosexuals.
If an artist had a gallery where he sold his portraits and other paintings, he would be engaged in commerce, and his gallery would be a business. In some states that would make it a public accommodation. But if the artist opposed same-sex marriage, I doubt very much the state law could require him to paint a picture commemorating a homosexual couple's wedding. He would have a very strong argument that the law compelled him to propound a point of view he disagreed with, and therefore, as applied to him, unconstitutionally abridged his freedom of speech.