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The amicus brief signed by more than 100 Republicans urging the Supreme Court to overturn Proposition 8 got a lot of attention last week. As well it should. The prominent GOP signatories represent the enlightened wing of a party that has grown increasingly exclusive when inclusion is key to its survival as a national party. But acclimation for that brief obscured the important amicus brief filed by the NAACP Legal Defense Fund (LDF) in Windsor v. the United States (a.k.a. the Defense of Marriage Act, or DOMA, case).

The 73-year-old civil rights organization was founded to battle racial discrimination in the courts. No surprise, then, that the LDF was at the Supreme Court last week fighting for the Voting Rights Act. But it also had no problem arguing that the struggle for marriage equality for same-sex couples is in line with the battle against the “separate but equal” doctrine that blocked blacks from pursuing the American dream.

Of course, the nature of discrimination against gays and lesbians differs fundamentally from de jure racial segregation, just as racial discrimination differs from discrimination based on sex and other suspect classifications to which heightened scrutiny applies. But DOMA and other laws that purposefully infringe on the rights of gay people are analogous to the racial caste system effectuated under “separate but equal” in an important respect: they create and perpetuate a social hierarchy that is premised on the superiority of one group over another.

By virtually any measure, gays and lesbians have been subjected to systemic discrimination throughout our nation’s history, resulting in their ongoing subordination as a class. And DOMA’s express purpose is to create and perpetuate a hierarchy that disadvantages gay people based on their sexual orientation…..

The LDF brief goes on to argue that because DOMA targets gay men and lesbians, the Supreme Court should apply heightened scrutiny (read, a more rigorous view) to the discriminatory law.

The application of heightened scrutiny to degrading and oppressive laws has been instrumental in pushing past discriminatory barriers of all kinds by signaling that such laws should have no place in our society. More searching judicial review is critical to advancement of civil rights for all, and to our progress as a nation.

Many African Americans don’t like that the lesbian, gay, bisexual and transgender (LGBT) community has called its quest for equality a civil rights movement. They say it’s not the same. But as the LDF brief plainly states and as I have written before, there is a shared struggle for civil rights between African Americans and gays. What links the two struggles is a demand for equal protection under the law.
But many blacks weren’t buying it. They didn’t like that the lesbian, gay, bisexual and transgender (LGBT) community has called its quest for equality a civil rights movement. They were adamant that the two were not the same or even analogous, and poll numbers reflected that opposition.

And then came President Obama.

“I think same-sex couples should be able to get married,” he told Robin Roberts of ABC News last May. He recognized that others who believe marriage is between one man and one woman, especially pastors and friends, “are not coming at it from a mean-spirited perspective.” He pointed out many of those folks are pastors and friends he “deeply respect[s].” When Roberts said, “Especially in the black community,” the president’s response was all about fairness.

Absolutely. But– but I think it’s important for me– to say to them that as much as I respect ’em, as much as I understand where they’re comin’ from– when I meet gay and lesbian couples, when I meet same-sex couples, and I see– how caring they are, how much love they have in their hearts– how they’re takin’ care of their kids. When I hear from them the pain they feel that somehow they are still considered– less than full citizens when it comes to– their legal rights– then– for me, I think it– it just has tipped the scales in that direction.

The Obama effect impact of the president’s declaration was almost immediate. A Post-ABC News poll released a week later showed that 54 percent of African Americans supported the Obama’s position on same-sex marriage. A Public Policy Polling survey of Maryland voters on marriage equality conducted more than two weeks after that announcement saw a 16-point swing in African American support, from 39 percent in March to 55 percent in May. Maryland’s law legalizing same-sex marriage survived a voter referendum with 52.4 percent approval. The Free State was one of three to say “I do” to gay nups last November.

While blacks opposed “Question 6” 54 percent to 46 percent, exit polls showed a massive gender gap with 51 percent of black women voting yes and 60 percent of black men voting no. Still, the measure won predominantly black Baltimore County (57 percent) and almost won majority-black Prince George’s County (49 percent).

In 2008, Proposition 8, the state constitutional ban on same-sex marriage in California, was approved with 52 percent of the vote. About 58 percent of African Americans supported the measure. But look at what’s happened four years later. The Field Poll released last week showed that 61 percent of California voters are now in favor of marriage equality. Even better, support among African Americans and Asian Americans stands at 64 percent. That’s a 23 percent increase since 2010.

All this is part of the dramatic backdrop for the amicus briefs filed last week and the arguments the Supreme Court will hear later this month. Like the president, the nation is evolving on the question of marriage equality. Still, the LDF is no stranger to defending the equal protection rights of gay men and lesbians. The organization, which is separate and apart from the NAACP, has filed amicus briefs in related cases since Romer v. Evans in 1996. But given the amazing changes in the last year, the LDF’s brief in the DOMA case is especially powerful.

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Jonathan Capehart is a member of the Post editorial board and writes about politics and social issues for the PostPartisan blog.