Gabriel's second claim dealt with my argument that integration is viewed as less of a problem than segregation. He argues that I misconstrued this point since the Court still applied strict scrutiny in Grutter and that integration is less of a problem only to the extent that it's easier to justify as a compelling state interest.
This argument is true, but when I made this argument in my post, I had already argued in the alternative based on the premise that the Court would find gender discrimination. Before embarking on the integration-segregation argument I stated:
"But let's say we should frame it as discrimination based on gender and therefore subject to intermediate scrutiny."
I was unclear on this point, but the integration argument is within the context of justifying the classification based on an important governmental objective. My point was that integration was held to a lower standard than segregation; that means the state will have an easier time passing intermediate scrutiny.
I did not properly develop this point, so I'll do so now. Justice O'Connor in Grutter argued,
"Absent searching judicial inquiry into the justification for such race-based measures, we have no way to determine what “classifications are ‘benign’ or ‘remedial’ and what classifications are in fact motivated by illegitimate notions of racial inferiority or simple racial politics. We apply strict scrutiny to all racial classifications to “ ‘smoke out’ illegitimate uses of race by assuring that [government] is pursuing a goal important enough to warrant use of a highly suspect tool.” Ibid. (internal citations omitted)"
So the issue here is whether integration is an "illegitimate use of gender."
Like any other test, which idea would constitute an "important governmental objective" that allows discrimination that is "substantially related to achievement of that objective" is up to the justices. Justice Ginsburg in Gratz argued that exclusion and inclusion are entirely different concepts and whereas exclusion is almost always wrong, inclusion can be better justified. Her argument was also made in reference to a racial classification, where the standard is substantially higher.
Society has many reasons to integrate the sexes; one such reason is procreation. Every society has an interest in surviving and to exist it needs to breed new members. That idea is best realized through opposite sex couples having children. Society therefore supports procreation by promoting integration. Integration is this vein should be promoted.
Obviously if we allowed SSM, men and women would still integrate since the vast majority of the public is heterosexual. But one could also argue that without preferences universities would still accept members of the preferred minorities. The idea is that a lower number would be selected and that goes against a state interest.
If we allowed SSM, less men would integrate with women and vice versa. The reason is that (some) homosexuals have historically married people of the opposite gender when no other avenue was available. Whether it was societal pressure or legal recognition, homosexuals did marry members of the opposite gender and procreated. Today we have a much lower level of societal pressure, but for now the only legal avenue for recognition is heterosexual marriage. It would stand to follow that some homosexuals who would enter into SSMs if they had the opportunity might do so.
Without question there are people who are attracted to both sexes or people who are more attracted to their gender but are still attracted to the opposite gender. Many of these people would choose marriage and the benefits it provides over a non-marriage relationship with a member of his/her sex. That choice has a much higher probability of resulting in procreation than a same sex relationship.
But if we allowed SSM, many of those people would likely choose to enter into that relationship. Society is therefore promoting procreation by leaving open only one avenue for marriage.
Gabriel, as well as other advocates of SSM, argue that the fact we allow sterile couples to marry goes against this argument. I do not see how. Just because the state does not choose to promote its interest in every possible way does not mean it cannot promote its interest in any way.
So if we allowed SSM, we would have a lower level of procreation than we have under the current laws in most states. Integration is therefore "substantially related to achievement of that objective," and not an illicit use of gender. The last point Gabriel dealt with was my argument that marriage is by definition between men and women. Perhaps I was unclear on this point as well, since Gabriel did not really respond to my argument at all, so I will quickly reiterate.
Marriage throughout history has been between men and women. The reason for this institution is procreation. Since only heterosexual couples can procreate, the institution was limited to them. But in creating marriage, society drafted a broad rule and did not, for the most part, make exceptions within the male/female marriage concept.
I argued that in other fields the law assumes procreative ability even after it has become impossible. I proposed a possible explanation based on judicial economy; that is courts find a presumption of fertility when dealing with heterosexual people. But that presumption only exists when the marriage is between heterosexual people, who can normally procreate, but not homosexual couples because, in general, they cannot procreate.
The point of this argument is to show that even if the denial of SSM is gender discrimination, there's no discrimination here because the right given to heterosexual couples cannot, by definition, be given to same-sex couples.
Gabriel asks if California could have used this argument by saying that cells are, by definition, between members of the same sex. Of course they could, but as a practical matter the courts will always be "strict" in applying strict scrutiny when dealing with race.
But in reality the situations are different. Creating a definition is fundamentally different than applying a longstanding one. In the case of marriage, the definition preceded the union and the Constitution. The state did not create this definition to get around a gender classification. The definition preceded the laws of all our states.
To use my earlier example could someone who wished to marry a tree argue that he is being discriminated against and then require the state to provide a rational basis for this classification? Of course not. Can anyone imagine a court going through the whole Equal Protection analysis and then forcing the state to provide a rational basis for its law? I certainly cannot. The court would likely just point out that trees simply cannot marry.
There's no difference between a man-tree marriage and a SSM. Legally, neither cannot exist by definition.
On the point that states sometimes allow people to marry even if they cannot procreate and sometimes only if they cannot procreate, that just shows there are exceptions. As a legislative matter, that might be a solid argument to allow SSM, since it proves we already have exceptions. But constitutionally that does not show marriage is not solely an opposite sex institution.