(CBS News) WASHINGTON - The Supreme Court held a second day of hearings on same-sex marriage. Wednesday's case involves the Defense of Marriage Act, which defines marriage as between a man and a woman. The woman who is challenging the law was present at the court.
Edie Windsor met Thea Spyer in the 1960s in Manhattan. They dated two years and then, Windsor says, made a commitment.
"I said, 'If it goes like this, I think I would like to be engaged for a year, and if that still works and feels this joyous, then I think I'd like to get married and spend the rest of my life with you,'" Windsor recalled.
They did spend their lives together -- the next 40 years -- and in 2007, finally married legally in Canada.
When Spyer died in 2009, she left her estate to Windsor. But the federal government said Windsor owed $363,000 in inheritance taxes because Windsor, under federal law, was not considered married.
"If Thea's name had been Theo, I would have paid no tax," said Windsor.
Today, Windsor, 83, was at the Supreme Court for arguments in her case challenging the constitutionality of the Defense of Marriage Act, which denies federal benefits to gay and lesbian married couples even in states where same-sex marriage is legal.
In court, a majority of the justices indicated the law was in jeopardy.
Liberal Justice Ruth Bader Ginsburg suggested it violated the Constitution's Equal Protection Clause because it treated legal same-sex marriage differently from heterosexual marriage: " There are two kinds of marriages: the full marriage, and then this sort of skim-milk marriage."
Justice Elena Kagan appeared most hostile to the law, suggesting Congress in 1996 had no legal justification for passing it: "Well is what happened in 1996 -- and I'm going to quote from the House report here -- is that 'Congress decided to reflect an honor of collective moral judgment and to express moral disapproval of homosexuality.' Is that what happened in 1996?"
The other liberal justices, Stephen Breyer and Sonia Sotomayor, appeared to agree -- leaving all eyes on the conservative swing justice, Anthony Kennedy, who previously has sided with liberals on gay rights issues.
Kennedy repeatedly expressed concerns about the law, but for different reasons. He suggested Congress had no authority to pass it because the issue of marriage historically has been left to the states.
"The question is whether or not the federal government, under our federalism scheme, has the authority to regulate marriage," said Kennedy.
Now even though it looks like a majority of the justices are prepared to strike down the law, you never know for sure until you see the opinion -- Justice Kennedy is always difficult to predict. There are also serious procedural questions in this case -- questions about whether the court has jurisdiction to decide the case. Those questions took up nearly half the argument.