Join Yahoo! News this Tuesday at 12:30 p.m. ET right after the Supreme Court hears oral arguments in the first of two major same sex marriage cases. University of Chicago law professor Geoffrey Stone; University of California-Irvine law professor Erwin Chemerinsky; Chapman University law professor and National Organization for Marriage chairman John Eastman; Yahoo! News national affairs writer Liz Goodwin; and Yahoo! News senior editor for politics and national news Beth Fouhy will lead a discussion on whether the Supreme Court is likely to legalize gay marriage.