The law of sex discrimination has long suffered under the problem of distinguishing between discrimination based on sex and discrimination based on sexual orientation.

Twenty-two states and the District of Columbia, as well as over one hundred municipalities, have laws prohibiting discrimination in the housing market on the basis of sexual orientation. Those jurisdictions include California, Colorado, Connecticut, Delaware, the District of Columbia, Hawai‘i, Illinois, Iowa, Maine, Maryland, Massachusetts, Minnesota, Nevada, New Hampshire, New Jersey, New Mexico, New York, Oregon,...