Massachusetts Attorney General Martha Coakley plans to be at the U.S. Supreme Court for arguments on the federal Defense of Marriage Act.
The law prohibits same-sex couples in states where gay marriage is legal from receiving an array of federal benefits available to heterosexual married couples. The justices are hearing the case today.
Coakley and New York Attorney General Eric Schneiderman filed a brief with the high court last month calling for DOMA to be struck down.
Massachusetts in 2009 was the first state to challenge DOMA, saying the law discriminated against the thousands of couples that had married since the state legalized gay marriage.
Coakley and 13 other states also filed a brief seeking an overturn of California's ban on gay marriage. The Supreme Court heard that case on Tuesday.
Copyright 2013 Associated Press. Associated Press.