This paper examines the extent to which equality claims have been used to require the legalization of same-sex marriage in
American state and federal legal doctrine, as a matter of comparative interstate constitutional law. It also examines whether
and how equality principles have been used to require the legalization of same-sex marriage in other nations, an exercise of
comparative intercountry constitutional law. It then considers whether equality principles justify requiring the legalization of
same-sex marriage as a matter of general jurisprudential principles.