This one is for the ages. Justice Anthony Kennedy's opinion for the U.S. Supreme Court announcing a right to gay marriage in Obergefell vs. Hodges will take its place alongside Brown vs. Board of Education and Loving vs. Virginia in the pantheon of great liberal opinions.
The only tragic contrast with those landmarks in the history of equality is that both of those were decided unanimously. Friday's gay-rights opinion went 5-4, with each of the court's conservative justices writing a dissent of his own.
Eventually, legal equality for gay people will seem just as automatic and natural as legal equality for blacks. But history will recall that when decided, Obergefell didn't reflect national consensus, much less the consensus of the court itself.
Kennedy's opinion offered two different yet interrelated constitutional rationales, one focused on the institution of marriage, the other on the equality of gay people. First, he made the case that marriage is a fundamental liberty right under the due process clause of the Constitution, which says no one may be deprived of life, liberty or property without due process of law. Applying what's known as "substantive" due process analysis, Kennedy held that the government may not infringe the liberty to marry, absent a compelling interest and along narrowly tailored lines to achieve that interest. Because no such interest exists, gay people as well as straight people must have the right to marry. This same approach was used by the court in the Loving case, which struck down laws barring interracial marriage. It was symbolically important for Kennedy to connect same-sex marriage to marriage between the races.
Kennedy's favorite concept of dignity figured large in the finding that marriage is a fundamental right. "The lifelong union of a man and a woman always has promised nobility and dignity to all persons, without regard to their station in life." The reference to dignity connected the decision to Kennedy's earlier gay-rights decisions, which featured the concept centrally. It is now an important part of our constitutional law — no matter that it doesn't appear in the Constitution.
Another crucial feature of the opinion was Kennedy's recognition that marriage has evolved over time. This acknowledgment counteracted the conservatives' emphasis on tradition in their dissents. It also resonated with the doctrine of due process, which looks to evolving tradition to identify the content of protected liberty.
When it came to equality, Kennedy avoided announcing that laws burdening gay people would be subject to especially strict scrutiny, like laws burdening racial minorities, or even what's called intermediate scrutiny, like laws differentially burdening the sexes. Instead, he spoke of the "synergy" between due process and equality. In legal terms, this almost certainly meant that once a fundamental right is invoked, any distinction between people for any reason requires strict scrutiny — a longtime doctrinal norm.
But Kennedy didn't quite say so, probably because he wanted to preserve the legacy of earlier gay-rights opinions in which he never said that he was engaged in close scrutiny, but rather said that the laws were discriminatory on their face. In a sense, Kennedy in Friday's opinion was trying to defend and sharpen the legal rationales of those earlier decisions, which have been criticized especially strongly by Justice Antonin Scalia.