Lots of skepticism from Supreme Court justices on the Defense of Marriage Act, which defines marriage as between a man and woman.
"The Federal Government is intertwined with the citizens' day-to-day life, you are at - at real risk of running in conflict with what has always been thought to be the essence of the State police power, which is to regulate marriage, divorce, custody," Justice Anthony Kennedy said.
The case against the Defense of Marriage Act was brought by an elderly New York woman, Edith Windsor who was hit with a $363,000 federal estate-tax bill when her same-sex spouse passed away in 2009.
Now had the feds recognized Windor's marriage, which was valid in New York - she would have owed nothing.
"I didn't feel any hostility, okay, or any sense of inferiority, you know, what do these people want? I felt, felt, felt we were very respected and, and I think, I think it's gonna be good," Windsor said.
Outfront tonight: Senior Legal Analyst Jeffrey Toobin, who was in the courtroom.
Supreme Court justices heard arguments today for and against California's 2008 ban on same-sex marriage known as Proposition 8.
The justices have the power to make same-sex marriage the law of the land. Currently, it's only the law in nine states and Washington D.C.
Some justices seemed wary of issuing a broad ruling.
"This was a deeply divided Supreme Court, and a court that seemed almost to be groping for an answer here," said CNN Senior Legal Analyst Jeffrey Toobin after following 80 minutes of arguments.
OutFront tonight: Senior Legal Analyst Jeffrey Toobin.
On Tuesday, the Supreme Court is schedule to hear the case against Proposition 8 - the California law that banned same-sex marriage. And on Wednesday, the high court takes on the 1996 Defense of Marriage Act.
A new CNN poll shows a majority of Americans, 57% - have a family member or close friend who is gay. That number is up from 45% in 2007.
As our Kyung Lah found out, this polarizing and personal issue of same-sex marriage is bringing families together - and tearing them apart.
According to a new study from the American Academy of Pediatrics parents sexual orientation has no effect on a child's development.
In a report released today, the nations most influential pediatricians group says gay couples should be allowed to marry in order to ensure the best health and well-being of a child.
Outfront Tonight: Peter Sprigg with the family research council, Keli Goff is a correspondent for The Root.com, and Reihan Salam is a CNN contributor and writer for the National Review.