The cases under review were brought by the city of San Francisco, two dozen gay and lesbian couples, Equality California and another gay rights group in March 2004 after the court halted San Francisco's monthlong same-sex wedding march that took place at Mayor Gavin Newsom's direction.
The legal issues involved in the California case differed slightly from court cases brought in other states, like Vermont and Massachusetts, because California's statutory Domestic Partnership scheme already provides same-sex couples access to essentially all the rights, privileges, and responsibilities as opposite-sex married couples. In this way, the dispute was less about substantive tangible rights, which same-sex couples already theoretically enjoyed in California, and more about the constitutionality of providing a separate-but-equal statutory scheme for same-sex couples.
As the Court put it, "the question ... is whether ... the failure to designate the official relationship of same-sex couples as marriage violates the California Constitution."
Also of interest is that the California Court (unlike Massachusetts) framed its constitutional equal protection analysis of classifications or discrimination on the basis of sexual orientation as one deserving a greater scrutiny, or "strict" judicial scrutiny, requiring the state to demonstrate the classification to be "necessary" for the purposes of some "compelling state interest".
The court reasoned that, in "Applying this standard to the statutory classification here at issue, we conclude that the purpose underlying differential treatment of opposite-sex and same-sex couples embodied in California’s current marriage statutes — the interest in retaining the traditional and well-established definition of marriage — cannot properly be viewed as a compelling state interest for purposes of the equal protection clause, or as necessary to serve such an interest."
In reaching its decision, the Court drew heavily from the tradition of cases overturning laws barring interracial marriage, (like Perez v. Sharp and Loving v. Virginia) when it proclaimed that "Tradition alone, however, generally has not been viewed as a sufficient justification for perpetuating, without examination, the restriction or denial of a fundamental constitutional right."
The Court decided in its majority opinion, "that although the provisions of the current domestic partnership legislation afford same-sex couples most of the substantive elements embodied in the constitutional right to marry, the current California statutes nonetheless must be viewed as potentially impinging upon a same-sex couple’s constitutional right to marry under the California Constitution.
Accordingly, we conclude that the right to marry, as embodied in article I, sections 1 and 7 of the California Constitution, guarantees same-sex couples the same substantive constitutional rights as opposite-sex couples to choose one’s life partner and enter with that person into a committed, officially recognized, and protected family relationship that enjoys all of the constitutionally based incidents of marriage."
The full text of the California Supreme Court decision, In Re: Marriage Cases, can be viewed here in its entirety.