. >> i'm sherrill jennings.other big story of the day. >> what could be the final step that extends gay marriage nationwide. the supreme court tonight agrees to decide whether same-sex couples have a right to get married anywhere in the united states. >> right now 36 states, the district of columbia, allow gay couples to wed. lyanne has the latest. >> the supreme court is saying it's time to rule as a nation. if the supreme court sides with the couples who are appealing, we'll see a landmark civil rights decision. we haven't seen one since 1967 when the supreme court invalidated laws prohibiting interracial marriages. the case was lobbing versus virginia. the four cases from michigan, ohio kentucky and tennessee will be consolidated and heard in april. it involves 0 couple who's lost their appeals to marry or to have their marriages recognized in those states. for past ten years san francisco city attorney dennis herrera has been at the forefront of the legal battle for marriage equality. >> it is an issue that