Originally Posted by matchlight
This is all very true...
However to make a definitive statement that rational basis review is the standard that will apply is unknown at this time, that's what the SCOTUS will have to determine. Those better at the law then I can surely make an argument (and have done so in cases that have already been reviewd and upheld by the 10th and 4th Circuit courts.
First, as your unsourced quote (presumably it is from a SCOTUS case) points out, rational basis is not the level of scruitiny applied when laws work to inhibit a fundamental right. The SCOTUS has repeatedly recognized that Civil Marriage is a fundamental right (Zablocki v. Redhail and Turner v. Safley and Loving v. VIrginia).
Second, the independent area of examination is "suspected lines". Starting with Romer v. Evans the court began to recognize that laws that target homosexuals were unconstitional not even surviving a rational basis examination.
Romer v. Evans
Amendment 2 fails, indeed defies, even this conventional inquiry. First, the amendment has the peculiar property of imposing a broad and undifferentiated disability on a single named group, an exceptional and, as we shall explain, invalid form of legislation. Second, its sheer breadth is so discontinuous with the reasons offered for it that the amendment seems inexplicable by anything but animus toward the class that it affects; it lacks a rational relationship to legitimate state interests.
Lawrence v. Texas
The second post-Bowers case of principal relevance is Romer v. Evans, 517 U.S. 620 (1996). There the Court struck down class-based legislation directed at homosexuals as a violation of the Equal Protection Clause. Romer invalidated an amendment to Colorado’s constitution which named as a solitary class persons who were homosexuals, lesbians, or bisexual either by “orientation, conduct, practices or relationships,” id., at 624 (internal quotation marks omitted), and deprived them of protection under state antidiscrimination laws. We concluded that the provision was “born of animosity toward the class of persons affected” and further that it had no rational relation to a legitimate governmental purpose. Id., at 634.
Windsor v. United States
The responsibility of the States for the regulation of domestic relations is an important indicator of the substantial societal impact the State’s classifications have in the daily lives and customs of its people. DOMA’s unusual deviation from the usual tradition of recognizing and accepting state definitions of marriage here operates to deprive same-sex couples of the benefits and responsibilities that come with the federal recognition of their marriages. This is strong evidence of a law having the purpose and effect of disapproval of that class. The avowed purpose and practical effect of the law here in question are to impose a disadvantage, a separate status, and so a stigma upon all who enter into same-sex marriages made lawful by the unquestioned authority of the States.
Romer, Governor of Colorado, et al. v. Evans et al., 517 U.S. 620 (1996).
LAWRENCE V. TEXAS
UNITED STATES v. WINDSOR | LII / Legal Information Institute
The the first question the SCOTUS will have to answer: is marriage a fundamental right that applies to same-sex couples? Secondly, did the passage of laws that denied equal treatment under the law, which anyone will honestly recognize as starting after the Hawaii case in the early 90's, target same-sex couples along suspect lines.
The court has repeated said that Civil Marriage is a fundamental right - that could raise the bar above rational basis. Independently the courts have also found unconstitutional laws that target homosexuals for discrimination - that could also raise the bar above rational basis. Whether that would be heightened scrutiny (along the lines of gender) or strict scrutiny (along the lines of race and religion), we don't know yet.
Then of course they could use rational basis and point out that the law doesn't even meet that standard.