The US Supreme Court has declared that same-sex couples have a right to marry anywhere in the country, in a culmination of two decades of litigation over marriage, and gay rights generally.

"No union is more profound than marriage," wrote Justice Anthony Kennedy, joined by the court's four more liberal justices on Friday.

Notes from the field: Al Jazeera's Alan Fisher
It's three hours since the court delivered the verdict, but the crowd still in the hundreds don't want to leave.
For them this is the place where history was made and they want to soak it up for as long as possible.
They are smiling and cheering and waving rainbow flags. There have been rousing versions of "We shall overcome" and the US national anthem.
One woman told me: "I no longer feel like an outsider in my own country," while a man close to tears told me he's not gay but can't hide his delight for his gay friends. "They've waited for this day for a long time."
There are surprisingly few objectors here - certainly none that I can see or are making themselves known.
This is a celebration for the LGBT community and their supporters. The majority of Americans support gay marriage. Now the courts do, too.

Gay and lesbian couples already could marry in 36 states and the District of Columbia. The court's 5-4 ruling means the remaining 14 states, in the South and Midwest, will have to stop enforcing their bans on same-sex marriage.

President Barack Obama welcomed the decision on Twitter, calling it "a big step in our march toward equality".

Dissenting judges

Hundreds of activists gathered outside the Supreme Court building to celebrate the decision, chanting, "Love has won." The crowd also raised a large flag with the pink equal sign that has come to symbolise the gay marriage movement. Some wept.

Across the South and Midwest, gay couples rushed to marry at county clerk's offices and judge's chambers.


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The four dissenting justices each filed a separate opinion explaining their views.

"This court is not a legislature. Whether same-sex marriage is a good idea should be of no concern to us," Chief Justice John Roberts wrote in dissent.

"If you are among the many Americans - of whatever sexual orientation - who favour expanding same-sex marriage, by all means celebrate today's decision," Roberts said. "But do not celebrate the Constitution. It had nothing to do with it."

The cases before the court involved laws from several states that define marriage as the union of a man and a woman. Those states have not allowed same-sex couples to marry within their borders and they also have refused to recognise valid marriages from elsewhere.

Just two years ago, the Supreme Court struck down part of the federal anti-gay marriage law that denied a range of government benefits to legally married same-sex couples.

There are an estimated 390,000 married same-sex couples in the United States, according to the Williams Institute at the University of California, Los Angeles, which tracks the demographics of gay and lesbian Americans. An estimated 1 million same-sex couples, married and unmarried, live together in the United States, according to the institute.

Source: Al Jazeera and agencies