WASHINGTON -- Giving gay-rights advocates a breakthrough victory after a nearly three-decade campaign for legal protection, the Supreme Court ruled yesterday that the Constitution assures homosexuals a measure of equality in the nation's public life.
In the first-ever Supreme Court decision favoring a major homosexual-rights cause, the court's 6-3 vote struck down the most pervasive form of inequality for gay men, lesbians and bisexuals.
It nullified a Colorado constitutional amendment that denied those individuals nearly all forms of government protection against discrimination based on their sexual identities. All existing gay-rights laws in the state would have been repealed, and no new ones could have been created except by amending the state's constitution.
That amendment was one of a series of voter-initiated attempts across the country to wipe out gains that gay-rights activists have made in the enactment of anti-bias laws or policies at the state and local level.
Colorado's amendment, Justice Anthony M. Kennedy said for the majority, "classifies homosexuals not to further a proper legislative end but to make them unequal to everyone else. A state cannot so deem a class of persons a stranger to its laws."
Because the ruling appeared to be shaped narrowly to deal with Colorado's far-ranging attack on gay political action, it left much to be decided in future cases.
The decision contained no hints, for example, about the fate of the current policy -- the "don't ask, don't tell" rule -- that bars most homosexuals from the military. The decision also does not address other public policies that treat homosexuals differently, such as the denial of the option to marry legally, to teach in public schools, to have custody of children, and to have equal access to housing and jobs.
Gay-rights activists claimed a major legal breakthrough. Matthew Coles of the American Civil Liberties Union said the decision "marks a sea change in the struggle of lesbians and gay men for equality in America. It establishes as a general principle that lesbians and gay men are entitled to the same constitutional protections granted to everyone else."
Activists on the other side railed against the court. Gary L. Bauer, president of the Family Research Council, called the ruling the work of "an out-of-control, unelected judiciary." He added that it "should send chills down the back of anyone who cares whether the people of this nation any longer have the power of self-rule."
Kennedy read dispassionately a summary of his ruling from the bench. Then, speaking nearly twice as long, Justice Antonin Scalia read much of his dissenting opinion. The dissent was a scathing denunciation of the court for making new law and for disparaging the moral sentiments of the people of Colorado.
"I think it no business of the courts to take sides in this culture war," Scalia said.
Kennedy's majority included Justices Stephen G. Breyer, Ruth Bader Ginsburg, Sandra Day O'Connor, David H. Souter and John Paul Stevens.
Joining Scalia in dissent were Chief Justice William H. Rehnquist and Justice Clarence Thomas.
Since the gay-rights movement began as a political force after the riots sparked by a police raid on a gay bar, the Stonewall Inn, in New York City's Greenwich Village in 1969, the issue of homosexual rights under the Constitution has raised two core legal questions. The court touched on only one of those yesterday.
One issue is whether homosexuals are, like racial minorities or women, entitled to direct constitutional protection against government discrimination and, if so, how much protection they should get: the full guarantee of equality for minorities when race is used to deny rights, or the lesser guarantee of some equality for women when gender is used to deny rights.
That is the issue behind the most controversial disputes over gay rights: the challenge to discrimination against homosexuals in the military, and the plea for the right of homosexuals to marry or to have legal recognition for gay partnerships.
The court made only a small beginning yesterday in defining the constitutional status of homosexuality. And in doing so, it made no mention of the issues of gays in the military or same-sex marriage and partnerships.
Relying heavily on a brief submitted in the Colorado case by a group of law professors and written by Laurence H. Tribe of Harvard, the court said the Constitution does not allow government to pick "a single named group" and impose upon that group alone a broad "disability."
Whether the group is identifiable as homosexuals, or by some other single trait, the Constitution does not allow government to deny such a group protection "across the board."
The court did not have to say whether the Constitution extends more than this general form of equality to homosexuals. Still, the court never before had said that homosexuals share in that broad guarantee against discrimination.