It looks like we will have a decision on same-sex marriage by the end of June. My co-blogger Orin thinks the outcome will very likely be the nationwide legalization of same-sex marriage. I also think that outcome is now likely, but I want to amplify in this post a point made by Ilya yesterday: how the Court decides to reach that result is also important. Here’s your pre-decision guide to a post-decision world.

Nationwide legalization of same-sex marriage would be a huge victory for gay couples and their children, but it won’t immediately end discrimination against them or against gay people in general. What the Court signals in its decision about the constitutionality of other anti-gay legislation will have substantial legal effects down the road, just as the Court’s decision in Romer v. Evans put an end to growing state-wide efforts to repeal all civil rights law protecting gay people.

Around the country we are seeing proposed legislation that would not just protect religious objectors from anti-discrimination laws in general, but would target same-sex couples and their families for special mistreatment and vulnerability to discrimination. Consider just three recent examples of this disturbing trend.

A federal bill proposed in 2013, the Marriage and Religious Freedom Act (MARFA), which had 60 co-sponsors in the House, would prohibit any “adverse action” by the federal government against any “person” (defined to include businesses and even joint stock companies) who acts on the basis of a religious belief specifically opposing same-sex marriage or opposing sexual relations outside of opposite-sex marriages. In Virginia, one legislator has proposed to prohibit the state from refusing to issue or renew a professional license to anyone who acts on the basis of “religious or moral convictions of such person with respect to same-sex ‘marriage’ or homosexual behavior.”  In Texas, a pending bill would cut off the pay of any state worker who issued a marriage license to a same-sex couple, even under federal court order.

Each of these proposals is already vulnerable to constitutional attack under the RomerLawrenceWindsor line of decisions that has struck down laws excluding homosexuals from liberty rights or equal protection. But while a suspect-classification approach is immanent in its decisions, the Supreme Court has not said in precise terms that laws targeting individuals on the basis of sexual orientation are constitutionally suspect.

Here are some possible routes to a decision, in the order that I think they would be most helpful to future litigants.

(1) Sexual orientation discrimination

The Supreme Court could clear up any remaining doubt by squarely holding that classifications based on sexual orientation are subject to heightened (or close or searching or intermediate) scrutiny. The analysis would be: first, laws denying marriage licenses to same-sex couples are a form of sexual-orientation discrimination because of the close connection between the classification and sexual orientation (like the connection between yarmulke-wearing and Jewishness); second, laws discriminating against gay people raise the usual concerns that justify heightened scrutiny; and third, the state can’t justify the discrimination under the heightened standard.

A suspect-classification decision would logically dispose of proposals like MARFA, the Virginia anti-gay licensing bill, and the anti-gay government-workers bill in Texas. Laws like that would then either be declared unconstitutional as written or would have to be written so as not to target same-sex couples, in which case they might be subject to other constitutional attacks.

A similar result might be reached if the Supreme Court decided that anti-gay marriage laws are really a form of sex discrimination. I think this rationale is much less likely and not as persuasive, but there’s a cold logical appeal to it.

(2) Animus

The Court could hold that the exclusion of gay couples from marriage rests on animus. I’ve suggested arguments along these lines a few times on this blog (for example, see here and here) and in a Supreme Court Review article available here. Yesterday, Steve Sanders encapsulated and expanded upon the point in a post at SCOTUSblog.

This line of analysis captures what really drove the adoption of the various state mini-DOMAs and anti-SSM constitutional amendments circa 1996-2008, when the country was seized by an anti-SSM panic. It also helps explain why some states are unwilling even now to allow same-sex marriage.

But animus analysis is very contextual and does not pronounce broad legal principles that commit the Court to future results. That is part of its appeal. Depending on how an animus decision is written, it might well help with challenges to anti-gay proposals in the future. But it would probably leave things more uncertain than a straightforward suspect-classification result would.

(3) Rational basis

The Court could hold that there is no rational basis for excluding same-sex couples from marriage.  It could hold, for example, that the exclusion is not rationally related to the state’s interest in responsible procreation or to a generalized interest in moving slowly on reform in this area. (The inability of same-sex marriage opponents to set forth a plausible rational basis has been surprising.)

It’s not clear how applicable such a holding, specific to the justifications for marriage, would be to laws excusing religious-objectors from issuing marriage licenses or shielding licensed marriage counselors from having to serve same-sex couples. Those laws might also be irrational, of course, but the arguments would not be quite the same since the state interests would be distinct. Unless the Court is going to use rational-basis much more aggressively in the future, I would not want to have to rely on the doctrine.

(4) Fundamental right

A fourth possible outcome is that the Court could decide that same-sex couples have a fundamental right to marry.

Of the four possibilities, this one would seem the least directly helpful to beating back the kinds of targeted post-marriage statutes we may soon see. For one thing, such statutes may not address marriage directly, instead giving objectors broader exemptions from civil rights laws protecting gay people. Even targeted laws allowing businesses or government workers to refuse services to same-sex couples only in relation to their marriages would not altogether deny the right them to marry, although such laws might substantially burden the right (the proposed Texas law is especially egregious as an interference with the right to marry, in addition to its other constitutional defects).

The post-decision world, I’ve predicted, begins at 10 a.m. (EDT) on June 29, 2015.