India's Supreme Court on Thursday struck down a colonial-era law that made gay sex punishable by up to 10 years in prison, a landmark victory for gay rights that one judge said would "pave the way for a better future."

The 1861 law, a relic of Victorian England that hung on long after the end of British colonialism, was a weapon used to discriminate against India's gay community, the judges ruled in a unanimous decision.

"Constitutional morality cannot be martyred at the altar of social morality," Chief Justice Dipak Misra said, reading the verdict. "Social morality cannot be used to violate the fundamental rights of even a single individual."

As the news spread, the streets outside the courthouse erupted in cheers as opponents of the law danced and waved flags.

"We feel as equal citizens now," said activist Shashi Bhushan. "What happens in our bedroom is left to us."

In its ruling, the court said sexual orientation was a "biological phenomenon" and that discrimination on that basis violated fundamental rights.

"We cannot change history but can pave a way for a better future," said Justice D.Y. Chandrachud.

The law known as Section 377 held that intercourse between members of the same sex was against the order of nature. The five petitioners who challenged the law said it was discriminatory and led to gays living in fear of harassment and persecution.

Jessica Stern, the executive director of the New York-based rights group OutRight Action International, said the original law had reverberated far beyond India, including in countries where gay people still struggle for acceptance.

"The sodomy law that became the model everywhere, from Uganda to Singapore to the U.K. itself, premiered in India, becoming the confusing and dehumanizing standard replicated around the world," she said in a statement, saying "today's historic outcome will reverberate across India and the world."

The court's ruling struck down the law's sections on consensual gay sex, but let stand segments that deal with such issues as bestiality.