At least one justice expressed some hesitancy to overturn the will of the voters.
"The state constitution talks about 'the great power of the people' and their right to amend the guiding principles," Justice Joyce L. Kennard said. "As judges, our power is very limited. We would like to hear from you why this court can willy-nilly disregard the will of the people to change the constitution."
The hearing was broadcast live on a state-operated cable TV channel and streamed live on the Internet. It was also displayed on a huge JumboTron video screen in downtown San Francisco's Civic Center Plaza, where people on both sides of the issue gathered to watch and held signs lobbying the justices to take their side.
Dana Tibbits, who drove 400 miles from her home in Ventura County to join the crowd of Proposition 8 supporters, told ABC's KGO-TV she was there for the "approximately 7 million voters whose voices need to be heard."
"I'm concerned about the justices, the weight of our vote and the weight of our decision," Tibbits said.
On the other side, Ronald Cruz, 31, a law student at UC Berkeley, told KGO-TV he wanted the measure overturned.
"The rallies and marches make it clear we are not taking second-class treatment anymore and that is what drives court decisions on civil rights," he said.
The court is due to issue a ruling within 90 days of today's proceedings.
Chief Justice Ronald M. George said that the court's decision on whether Proposition 8 deprives gay citizens of an inalienable right "is going to have implications for future efforts if everything that could conceivably be characterized as an inalienable right is outside the people's initiative power."
Along with the constitutionality arguments, the court also heard opinions on whether the 18,000 same-sex marriages performed before the November election should remain legally recognized even if the justices uphold Proposition 8.
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