By definition, gay individuals are persons who are sexually attracted to persons of the same sex and thus, if inclined to enter into a marriage relationship, would choose to marry a person of their own sex or gender. 59 A statute that limits marriage to a union of persons of opposite sexes, thereby placing marriage outside the reach of couples of the same sex, unquestionably imposes different treatment on the basis of sexual orientation. In our view, it is sophistic to suggest that this conclusion is avoidable by reason of the circumstance that the marriage statutes permit a gay man or a lesbian to marry someone of the opposite sex, because making such a choice would require the negation of the person's sexual orientation. Just as a statute that restricted marriage only to couples of the same sex would discriminate against heterosexual persons on the basis of their heterosexual orientation, the current California statutes realistically must be viewed as discriminating against gay persons on the basis of their homosexual orientation.
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Having concluded that the California marriage statutes treat persons differently on the basis of sexual orientation, we must determine whether sexual orientation should be considered a “suspect classification” under the California equal protection clause, so that statutes drawing a distinction on this basis are subject to strict scrutiny.
In addressing this issue, the majority in the Court of Appeal stated: “For a statutory classification to be considered ‘suspect’ for equal protection purposes, generally three requirements must be met. The defining characteristic must (1) be based upon an ‘immutable trait’; (2) ‘bear[] no relation to [a person's] ability to perform or contribute to society’; and (3) be associated with a ‘stigma of inferiority and second class citizenship,’ manifested by the group's history of legal and social disabilities.
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Past California cases fully support the Court of Appeal's conclusion that sexual orientation is a characteristic (1) that bears no relation to a person's ability to perform or contribute to society (see, e.g., Gay Law Students, supra, 24 Cal.3d 458, 488), and (2) that is associated with a stigma of inferiority and second-class citizenship, manifested by the group's history of legal and social disabilities.
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We disagree, however, with the Court of Appeal's conclusion that it is appropriate to reject sexual orientation as a suspect classification, in applying the California Constitution's equal protection clause, on the ground that there is a question as to whether this characteristic is or is not “immutable.” Although we noted in Sail'er Inn, supra, 5 Cal.3d 1, that generally a person's gender is viewed as an immutable trait (id. at p. 18), immutability is not invariably required in order for a characteristic to be considered a suspect classification for equal protection purposes. California cases establish that a person's religion is a suspect classification for equal protection purposes (see, e.g., Owens v. City of Signal Hill (1984) 154 Cal. App. 3d 123, 128 [201 Cal. Rptr. 70]; Williams v. Kapilow & Son, Inc. (1980) 105 Cal. App. 3d 156, 161–162 [164 Cal. Rptr. 176]), and one's religion, of course, is not immutable but is a matter over which an individual has control. (See also Raffaelli v. Committee of Bar Examiners (1972) 7 Cal.3d 288, 292 [101 Cal. Rptr. 896, 496 P.2d 1264] [alienage treated as a suspect classification notwithstanding circumstance that alien can become a citizen].) Because a person's sexual orientation is so integral an aspect of one's identity, it is not appropriate to require a person to repudiate or change his or her sexual orientation in order to avoid discriminatory treatment. (Accord, Hernandez-Montiel v. I.N.S. (9th Cir. 2000) 225 F.3d 1084, 1093 [“exual orientation and sexual identity … are so fundamental to one's identity that a person should not be required to abandon them”]; Egan v. Canada, supra, 2 S.C.R. 513, 528 [“whether or not sexual orientation is based on biological or physiological factors, which may be a matter of some controversy, it is a deeply personal characteristic that is either unchangeable or changeable only at unacceptable personal costs …”].)