Same-sex couples are similarly situated to different-sex couples in terms of their economic status, their family decisions, their interdependence, and their valuing of marriage. It’s no surprise, then, that gay couples eagerly take advantage of the right to marry when they have it. Research shows that couples who marry - gay or straight - want to express their commitment to each other and to their family and friends. Same-sex couples want to marry to create a firm personal and legal foundation for their own lives and security for their current and future children.
Gay couples need access to civil marriage for the same reason that heterosexual couples need it: only the law can create a family relationship between adults that will be recognized by the state and third parties, like employers and insurance companies. Gay couples need the cultural status of marriage (not civil unions) because that’s what their friends and family understand and look for.
Overall, the evidence suggests that letting same-sex couples marry would be good public policy. Same-sex couples and their families will benefit, and the institution of marriage does not suffer. Gay couples’ interest in marriage is a vote in favor of the ongoing relevance of marriage in today’s world, a change that should strengthen, not weaken, the institution.