The evidence shows that the movement of marriage away from a gendered institution and toward an institution free from state-mandated gender roles reflects an evolution in the understanding of gender rather than a change in marriage. The evidence did not show any historical purpose for excluding same-sex couples from marriage, as states have never required spouses to have an ability or willingness to procreate in order to marry....Rather, the exclusion exists as an artifact of a time when the genders were seen as having distinct roles in society and in marriage. That time has passed.

The right to marry has been historically and remains the right to choose a spouse and, with mutual consent, join together and form a household....Race and gender restrictions shaped marriage during eras of race and gender inequality, but such restrictions were never part of the historical core of the institution of marriage....Today, gender is not relevant to the state in determining spouses’ obligations to each other and to their dependents. Relative gender composition aside, same-sex couples are situated identically to opposite-sex couples in terms of their ability to perform the rights and obligations of marriage under California law....Gender no longer forms an essential part of marriage; marriage under law is a union of equals.

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Plaintiffs do not seek recognition of a new right. To characterize plaintiffs’ objective as “the right to same-sex marriage” would suggest that plaintiffs seek something different from what opposite-sex couples across the state enjoy —— namely, marriage. Rather, plaintiffs ask California to recognize their relationships for what they are: marriages.