On Tuesday the Supreme Court heard oral arguments in Hollingsworth v. Perry, the case addressing whether California’s Proposition 8 can constitutionally outlaw same-sex marriages once the state has already authorized them. On Wednesday, the Court will hear arguments in United States v. Windsor to consider the constitutionality of the Federal Defense of Marriage Act (DOMA), which defines “marriage” as a legal union between a man and a woman. Depending on how the Court ultimately rules on these issues, married same-sex couples could be entitled to a host of federal benefits and protections, including the ability to file joint federal tax returns, receive spousal benefits through Social Security, obtain employer-sponsored medical benefits tax-free, and receive protection under the spousal provisions of ERISA relating to qualified retirement plans. The following summarizes the first day of arguments on this pivotal issue.

Standing

The justices spent a fair amount of time exploring whether the proponents of Proposition 8 have standing to defend the proposition (which outlawed same-sex marriage) when California’s officials choose not to defend it. The other major themes – if we can discern any from the wide-ranging questioning – are whether the Court should issue a broad decision that would apply to all states, just those with non-marriage equivalents for same-sex couples, just California, or whether the Court should simply let the political process take its course.

The crux of the standing issue is whether the proponents of the ballot initiative can pursue their claim once the initiative has passed if state officials are no longer interested in defending its constitutionality. While this might seem like an odd procedural issue, given tomorrow’s argument in United States v. Windsor (addressing DOMA), the fact is that dismissal of Hollingsworth on standing grounds, followed by affirmance of the lower court’s holding in Windsor, could leave the issues to continue to percolate through the various states until there is a semblance of unity on the topic. The problem that this could create is that without addressing the part of DOMA that allows one state to ignore a same-sex marriage validly created in another state, we are left with a situation where same-sex married couples would be at a significant detriment if they wanted to move to (or even visit) another state where their marriage is not recognized.

Scope

On the question of the scope of the decision, attorney Charles Cooper, arguing for the Proposition 8 proponents, seemed to be urging the Court to assume that in order to rule for the other side, the Court would have to strike down same-sex marriage prohibitions nationwide, and that to do so “would put a stop to that ongoing democratic debate” about whether the “age-old” definition of marriage should end. His theme was that the Court should not reach that conclusion unless the Court is convinced that “no rational, thoughtful, person of good will could possibly disagree with [same-sex marriage proponents] on this agonizingly difficult issue.”

Justice Kennedy, who could provide the swing vote in this case, noted that he was struggling with the question of whether the issue can be viewed as a gender-based classification (presumably because the only difference between two similarly-situated citizens of the same sex regarding their right to marry is the gender of the spouse). Later, Justice Kennedy pointed out that the 40,000 children of same-sex relationships in California have an interest in their parents having access to the benefits of marriage. Justice Sotomayor may have had these concerns in mind when she pressed Mr. Cooper to articulate why allowing same-sex marriage would harm the state’s interest (recognizing that it might not promote the state’s interest in responsible procreation – which seemed to be the only hook that Mr. Cooper was hanging his hat on). Justice Kennedy quickly picked up this question and pressed Mr. Cooper to answer it – and his only answer seemed to be that it is too soon to tell if there are any adverse consequences to allowing same-sex marriages. Justice Scalia tried to help him out by observing that if you have to allow same-sex marriages, you also have to allow adoption by same-sex married couples, and that there is “considerable disagreement among sociologists” about whether this is damaging to children.

All of the parties homed in on Loving v. Virginia as the most relevant prior decision. When Loving was decided, 16 states prohibited interracial marriage. The Court decided in that case that no state could prohibit interracial marriage – so the question before the Court now is whether the prohibition of same-sex marriage carries the same absence of reasonable justification that the prohibition of interracial marriage had in Loving. Mr. Cooper distinguished Loving by arguing that it cannot be said that in every relevant factor, same sex couples are similarly situated to opposite sex couples. It is “an agonizingly difficult, for many people, political question [that is] properly decided by the people themselves.” Solicitor General Donald Verrilli observed that at the time Loving was decided, the state’s argument was that it could be harmful to children to raise them in interracial homes and therefore the Court should wait – comparable to the arguments being raised by the opponents of same-sex marriage.

The Justices also spent some time discussing the fact that California provides all the substantive benefits to same-sex relationships in the form of domestic partnerships. Would the case come out differently in a state that does not provide benefits to domestic partnerships? Mr. Olson argued that it did not. This exchange led to another issue that troubled Justice Kennedy – if the decision is limited to California (or to California and other states that legitimize same-sex relationships), would states be penalized for not going far enough? He saw that as an “odd rationale on which to sustain this opinion.”

Mr. Olson responded that the fundamental right to marry applies in all states. Justice Sotomayor asked Mr. Olson that if marriage is a fundamental right, what state restrictions (such as minimum age) are permissible? Mr. Olson responded that such state restrictions prohibit conduct, and prohibiting marriage to gays and lesbians prohibits status, not conduct.

Merits

On the merits of the case, Solicitor General Verrilli argued that “every warning flag that warrants exacting scrutiny is present in this case.” A number of the Justices had a concern, however, with his apparent argument that only those states that recognized same-sex unions had to offer the rights of marriage to them. His response was that the door was not closed to a proper case brought in a state that offers nothing to same-sex relationships, but that where the state does recognize a relationship, there is no rational basis for distinguishing between those relationships and those of opposite-sex married couples.

As in many close cases, it is impossible to predict where the Court will come out. It may well dismiss the case on standing grounds, which would have the effect of leaving the issues to each state to decide. As a result – particularly if Windsor is affirmed – the U.S. would be permitted to recognize same-sex marriages in those states that have adopted it and perhaps put pressure on more states to recognize same-sex marriages. If the Court addresses the merits, it appears that Justice Kennedy may well cast the swing vote. Today’s oral argument indicates that he may be leaning toward allowing same-sex marriages, but it is very unclear how broadly his opinion would extend – to just California, all states allowing for same-sex unions, or everywhere.