Justice Anthony Kennedy in March. (Manuel Balce Ceneta/Associated Press)
Editorial writer and columnist

On one point the four dissenting justices in the gay marriage case are quite right: Justice Anthony M. Kennedy’s majority opinion shows how deeply the politics of identity have penetrated American culture and, now, jurisprudence.

You could even call his 28-page meditation “postmodern,” as Justice Samuel A. Alito Jr. did. Kennedy explicitly held that the “fundamental liberties” protected by the 14th Amendment “extend to . . . intimate choices that define personal identity and beliefs,” suggesting that the Constitution itself leaves gender and sexuality up to each individual, free from the constraints of tradition. Caitlyn Jenner, take note.

Of course, identity politics are not necessarily all that modern, or postmodern. They were present, so to speak, at the creation of the republic — right in the text of the Constitution. Certain identities were taken for granted, in references to “Indians not taxed,” to “natural-born citizens” and (by clear implication) to Africans held as slaves.

The difference between this form of identity politics and Kennedy’s is that the former was exclusionary and the latter is inclusionary. The Constitution both promised a measure of democracy and liberty previously unheard of in the world and allowed these to be denied to certain people based on their identity.

In 1868, with the ratification of the 14th Amendment — the provision at issue in the gay marriage case — the United States began its long move away from exclusionary identity politics. Codifying the results of the Civil War, that amendment guaranteed, first only on paper, then eventually also in practice, that black people were not an inferior caste but U.S. citizens entitled to liberty and equal protection of the law.

Eloquent as it may have been, Kennedy’s opinion was not terribly satisfying as a piece of legal reasoning. To cite one shortcoming, he made little serious effort to analyze gay marriage under the doctrine of equal protection, which might have required him to delve into whether gay men and lesbians constitute a “protected class” whose rights could be curtailed, but only if the justification survived various levels of judicial “scrutiny.”

As a broad interpretation of the 14th Amendment’s historical role in U.S. society, however, Kennedy’s opinion was rather more convincing. If you see the amendment (and its near twin, the 13th Amendment, which abolished slavery) as a repudiation of the principal pre-Civil War caste distinctions, then you can see it, as Kennedy did, as the foundation for subsequent removal of other identity-based barriers to full social participation, as those become apparent to an evolving society.

Kennedy’s repeated invocation of “dignity,” and his insistence that the case was not about just the legal rights but also the social status of gay men and lesbians — even their subjective “humiliation” — echoed, faintly but distinctly, the post-Civil War court’s discussions of “badges of slavery,” which the amendments of that era were meant to eliminate. It was as if he saw himself, and the court, striking down a sexual-orientation caste system.

Undoubtedly, the dissenters were right that Kennedy’s ruling nullifies the results of democratic processes in those more than 30 states that had voted to define marriage as a man-woman union only, just as surely as the 14th Amendment struck down the Southern states’ Black Codes (but, according to them, with much less support in the amendment’s actual text or history).

In theory, this should have been problematic for Kennedy. Just two years ago, he wrote the opinion striking down the Defense of Marriage Act, which had denied federal recognition to state-sanctioned gay marriages, in part because “Government, through our history, has deferred to state-law policy decisions with respect to domestic relations.”

What’s more, the only other issue that has stirred Kennedy more than gay rights over the years is state sovereignty. “Dignity” was his touchstone, then, too; in Alden v. Maine, for example, he declared that “Federalism requires that Congress accord States the respect and dignity due them as residuary sovereigns and joint participants in the Nation’s governance.”

Forced to pick between the dignity of states and the dignity of individuals, however, Kennedy chose the latter. Alas for the dissenters, their objections sounded procedural and formalistic in the context of increasingly pro-gay marriage opinion polls and, indeed, the facts on the ground (i.e., thousands of existing gay marriages). Many, if not most, of the gay marriage bans currently on the books would not pass if put to a vote today.

The dissenters implicitly conceded this by protesting that Kennedy and the court majority had permanently shut off democratic debate on gay marriage. Technically this isn’t true: Anti-gay marriage forces could campaign for a constitutional amendment overturning Friday’s ruling. Politically, though, that’s probably hopeless, as the justices know.

Anthony Kennedy transformed American society on Friday — believing passionately that he was doing the right thing, and, surely, equally confident that it would be popular.

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