New York: Edith Windsor, the gay-rights activist whose landmark case led the US Supreme Court to grant same-sex married couples national recognition for the first time and rights to a host of federal benefits until then only enjoyed by married heterosexuals, has died in New York. She was 88.

Her wife, Judith Kasen-Windsor, confirmed the death, at a hospital, but did not specify a cause.

Windsor, the widow of a woman with whom she had lived much of her life, became the lead plaintiff in what is widely regarded as the second most important Supreme Court ruling in the national battle over same-sex marriage rights. The Windsor decision, handed down in 2013, was limited to 13 states and the District of Columbia. But in a more expansive ruling in 2015, in Obergefell v Hodges and three related cases, the Supreme Court held that same-sex couples had a constitutional right to marry anywhere in the nation.

Like countless others, Windsor had been snared by the Defence of Marriage Act of 1996, which barred same-sex married couples from federal recognition as "spouses", effectively excluding them from federal benefits available to married heterosexuals.

After living together for 40 years, Windsor and Thea Spyer, a psychologist, were legally married in Canada in 2007. Spyer died in 2009, and Windsor inherited her estate. But the Internal Revenue Service denied her the unlimited spousal exemption from federal estate taxes available to married heterosexuals.

She sued, claiming that the law, by recognising only marriages between a man and a woman, unconstitutionally singled out same-sex marriage partners for "differential treatment". Affirming two lower court rulings, the Supreme Court, in the United States v Windsor, overturned the law in a 5-4 ruling.

By striking down the act's definition of marriage as a union of a man and a woman, the Supreme Court invalidated the entire law and for the first time granted same-sex marriage partners the recognition and benefits accorded married heterosexuals. But the decision did not say if there was a constitutional right to same-sex unions, and it left in place laws in 37 states that banned such marriages.

Gay-rights advocates acknowledged that the ruling had fallen short of their hopes for a constitutional guarantee of nationwide marriage equality. But it was, they said, a crucial step.

Then president Barack Obama called an elated Windsor with his congratulations. She became a national celebrity, a gay-rights matriarch, a grand marshal of New York City's LGBT Pride March and a runner-up to Pope Francis for Time magazine's person of the year in 2013.

"Married is a magic word," Windsor told a rally outside City Hall in New York a few days before Spyer died in 2009. "It has to do with our dignity as human beings, to be who we are openly."

Same-sex marriage became valid in New York state in 2011, too late for Windsor and Spyer. But Windsor's 2013 Supreme Court victory was followed by an avalanche of lawsuits attacking same-sex marriage bans in jurisdictions where they remained. And on June 26, 2015, the Supreme Court made same-sex marriage a constitutional guarantee all over the land.

It has to do with our dignity as human beings, to be who we are openly.

Edith Windsor

Kasen-Windsor, a banking executive whom Windsor married in 2016, is her only survivor.

New York Times