It is perhaps necessary to point out that there are two senses of the term "discrimination" which are often confused. In one sense, to exercise discrimination is simply to be discerning, to be quick at recognizing differences, to be cognitively alert. In the second sense, discriminatory action is action which is biased, prejudiced, unfair. It should be clear that legislators must, in the first sense, be discriminating. They must discern and recognize relevent [sic] distinctions and differences, they must draw lines, they must, in short, classify—and classify reasonably. What is forbidden as discriminatory is the bias and prejudice suggested by the second sense of that term.
(Joseph Tussman and Jacobus tenBroek, "The Equal Protection of the Laws," California Law Review 37 [September 1949]: 341-81, at 358 n. 35)
Note from KBJ: The word "discrimination" suffers from generic/specific ambiguity. Generically, to discriminate is to distinguish between things: wines, cars, baseball players, students, horses, apples, shoes. Discrimination in this sense is a good thing. A person who fails to be discriminating in this sense is said to be "indiscriminate," or to choose "indiscriminately." The distinction in question can be either relevant or irrelevant to the task at hand. Discrimination in the specific (normatively charged) sense is to distinguish between things on the basis of an irrelevant trait. When the things being distinguished are persons, and when the purpose of the distinguishing is to distribute benefits or burdens, the discrimination is invidious. The specific sense has all but swallowed up the generic sense, unfortunately. Many people today would feel uncomfortable describing themselves as "discriminating."
Is limiting marriage to heterosexual couples discriminatory? In the generic sense, yes, for in doing so, the law distinguishes between couples. Is it discriminatory in the specific (invidious) sense? That depends on whether you think there is a relevant difference between heterosexual couples and homosexual couples. If you think there is no relevant difference between them, then you will view the law as invidiously discriminatory, i.e., as unjust. If you think there is a relevant difference between them, then you will not view the law as invidiously discriminatory; you will view it as discerning, rational, and just. Can this issue be resolved? Only if the parties find common ground. The debate about homosexual "marriage" comes down to different views of the nature and purpose of marriage. If you view marriage as an institution designed to encourage procreation and promote the welfare of children, then you will not view the law as invidiously discriminatory. If you view marriage as a friendship between adults, with no necessary connection to children, then you will view the law as invidiously discriminatory.
I don't see much common ground between these views. They are rival conceptions of marriage. But the law cannot remain in equipoise. The legal question is who has the right and the responsibility to define "marriage." I say that the legislature does, and that judges should defer to legislative determinations in this area. In other words, there is a rational basis for the judgment, by a legislature, that marriage should be limited to heterosexuals. Since there is neither a fundamental right nor a suspect classification involved, the legislation should be upheld as against a due-process or an equal-protection challenge. The best analysis I have seen of this issue is by Massachusetts Justice Martha B. Sosman. See her opinion at page 20 of the Goodridge case.
