The Court gets to the two substantive options available to the justices in deciding the constitutionality of DOMA. Chief Justice Roberts and Justice Kennedy press Solicitor General Donald Verrilli on whether DOMA presents a federalism issue. General Verrilli is clear that the United States views DOMA as unconstitutional not because it intrudes on the states’ prerogative, but because discrimination and exclusion of same-sex couples from the institution of marriage is abhorrent and violates the Equal Protection Clause. This is in line with General Verrilli’s argument in Hollingsworth, in which he suggested that in the future, the Court should address whether bans on same-sex marriage violate the Equal Protection Clause beyond the context of Proposition 8. Justice Kennedy – and possibly his colleagues – seems to be at least probing the possibility of striking down DOMA on federalism grounds rather than issuing a ruling rooted in Equal Protection. General Verrilli’s argument is that DOMA has not defined marriage for the states, but constitutes federal discrimination against gays and lesbians in states where same-sex marriage has been enacted.

Justice Kagan also raises the issue of DOMA’s discriminatory motive. In Romer v. Evans, the Supreme Court held that laws targeting a particular group motivated by fear or animus are treated with more scrutiny than the minimal “rational basis” standard and are generally constitutionally illegitimate. Justice Kagan points directly to the language of the House in support of DOMA in 1996, which explains that Congress sought to express “moral disapproval of homosexuality.” Paul Clement concedes that if the Court finds this sufficient to constitute animus, the justices should invalidate DOMA.