THE US Supreme Court is treading cautiously as it considers gay marriage, with justices appearing hesitant to deliver a sweeping historic verdict on the emotionally-charged issue.
On a day long awaited by both sides of the debate, thousands of gay rights advocates waving US and rainbow flags descended on the Court, outnumbering a rally of religious activists opposed to same-sex marriage.
The Supreme Court will take months to issue a ruling but several justices indicated that they would be in no hurry to make a ruling that could extend the right to same-sex marriage to the entire country.
Justice Anthony Kennedy, whose remarks are closely watched as he is often the swing vote on the nine-member bench, voiced reluctance for the Court to step into "uncharted waters" on a case involving Californian law.
Kennedy said there was a lack of sociological evidence on same-sex marriage as "we have five years of information to weigh against 2000 years of history or more."
But Kennedy also expressed sympathy for an estimated 40,000 children living in California with same-sex couples, saying: "They want their parents to have full recognition and full status."
Justice Samuel Alito, a conservative, also spoke of a "lack of data" on same-sex marriage since it was first legalised in The Netherlands in 2001. Alito called marriage "essential for the preservation of society."
Liberal justices argued it was discriminatory to define marriage solely by whether a couple can bear children. Justice Elena Kagan said that by the same argument, the government could ban marriages of couples above age 55.
Nine US states and the capital Washington allow same-sex marriage.
Some rights advocates hope the Supreme Court will guarantee gay marriage across the United States, while opponents want to leave the decision to state MPs.
Opinion polls have repeatedly indicated that most Americans now accept the principle of same-sex marriage, including an overwhelming majority of younger Americans.
President Barack Obama last May became the first US president to publicly back gay marriage.
White House spokesman Jay Carney declined to predict how the Supreme Court would rule, but added that the treatment of gay and lesbians "goes to core principles about who we are as a country."
On a day long awaited by both sides of the debate, thousands of gay rights advocates waving US and rainbow flags descended on the Court, outnumbering a rally of religious activists opposed to same-sex marriage.
The Supreme Court will take months to issue a ruling but several justices indicated that they would be in no hurry to make a ruling that could extend the right to same-sex marriage to the entire country.
Justice Anthony Kennedy, whose remarks are closely watched as he is often the swing vote on the nine-member bench, voiced reluctance for the Court to step into "uncharted waters" on a case involving Californian law.
Kennedy said there was a lack of sociological evidence on same-sex marriage as "we have five years of information to weigh against 2000 years of history or more."
But Kennedy also expressed sympathy for an estimated 40,000 children living in California with same-sex couples, saying: "They want their parents to have full recognition and full status."
Justice Samuel Alito, a conservative, also spoke of a "lack of data" on same-sex marriage since it was first legalised in The Netherlands in 2001. Alito called marriage "essential for the preservation of society."
Liberal justices argued it was discriminatory to define marriage solely by whether a couple can bear children. Justice Elena Kagan said that by the same argument, the government could ban marriages of couples above age 55.
Nine US states and the capital Washington allow same-sex marriage.
Some rights advocates hope the Supreme Court will guarantee gay marriage across the United States, while opponents want to leave the decision to state MPs.
Opinion polls have repeatedly indicated that most Americans now accept the principle of same-sex marriage, including an overwhelming majority of younger Americans.
President Barack Obama last May became the first US president to publicly back gay marriage.
White House spokesman Jay Carney declined to predict how the Supreme Court would rule, but added that the treatment of gay and lesbians "goes to core principles about who we are as a country."
