An interview with Andrew Koppelman author of "Same Sex, Different States: When Same-Sex Marriages Cross State Lines."

Americans are profoundly divided over same-sex marriage, and now that gay civil unions and marriages are legal in some states, the issue has become increasingly urgent. Koppelman offers a sensible approach that will appeal to the best instincts of both sides. Drawing on historical precedents in which states held radically different moral views about marriage (for example, between kin, very young individuals, and interracial couples), Koppelman shows which state laws should govern in specific situations as gay couples travel or move from place to place.

Koppelman is professor of law at Northwestern University School of Law and author of Antidiscrimination Law and Social Equality and The Gay Rights Question in Contemporary American Law.