In the second day of back-to-back cases involving gay marriage, the Supreme Court Wednesday heard arguments for and against federal benefits for same sex couples.
Wednesday's oral arguments focused on the Defense of Marriage Act, which limits the definition of marriage as between a man and a woman.
Justices are considering whether the Defense of Marriage Act is discriminatory and therefore unconstitutional because it prevents the federal government from recognizing legally married same-sex couples.
Plaintiff Edie Windsor had to pay more than $300,000 in estate taxes when her same sex spouse died.
House Republicans are defending the law they passed 17 years ago.
Although hesitant, Justices indicated an interest in striking down the law, but first they spent nearly an hour debating whether they should even hear the case since the Justice Department refuses to defend DOMA.
Chief Justice Roberts called it "unprecedented" and Justice Scalia questioned how Congress can trust the laws it passes will get defended.
Justice Kennedy, thought to be swing vote, seemed to side with the more liberal justices expressing an interest in overturning DOMA, saying he was concerned that this law may infringe on state rights to decide who can and cannot legally marry.
A ruling is expected in late June.