California State Law California recognizes same-sex relationships under state law as follows: Same-Sex Marriage  Same-sex marriage is legal in California as of June 28, 2013. Note: On November 4, 2008, California state voters passed a ballot initiative known as Proposition 8, which amended the state constitution to define marriage as a union between a man and a woman. As a result, same-sex marriages were not permitted in California during this time.   Same-sex couples legally married in another jurisdiction are considered already legally married under California marriage licensing and certification laws. Note: During the time that same-sex marriages were not legal in California, the state recognized same-sex marriages performed in other jurisdictions as domestic partnerships.   Click here for more information. Domestic Partnerships Unmarried persons of the same sex may establish a domestic partnership in California. Registered domestic partners have the same rights, protections, and benefits, and are subject to the same responsibilities, obligations, and duties under law as are granted to and imposed upon spouses. A legal union of two persons of the same sex, other than a marriage, that was validly formed in another jurisdiction, and that is substantially equivalent to a domestic partnership under California law, is recognized as a valid domestic partnership in the state.  Click here for more information.