People carry placards in a march celebrating the ruling on Proposition 8 in West Hollywood, California, in this February 7, 2012, file photo. A challenge to Proposition 8, based on the federal Constitution, is one of two cases on gay marriage scheduled for oral arguments before the U.S. Supreme Court on March 26 and 27. The other takes on the federal Defense of Marriage Act, which defines marriage as between opposite-sex couples only. REUTERS/Jonathan Alcorn/Files