The California Supreme Court has uphold last November’s Proposition 8 result, siding with the majority of Californians and dashing the hopes of gay couples throughout the state by banning same-sex marriage.

However, it also decided that the estimated 18,000 gay couples who married in California before the law took effect will stay wed.

The announcement of the decision caused outcry among a sea of demonstrators who had gathered in front of the San Francisco courthouse waiting on the ruling.

The seven-member court refused to undermine California’s powerful citizen initiative process and upheld the initiative as a constitutional expression of the electorate’s will.

The court also rejected an argument by gay rights activists that the ban revised the California constitution’s equal protection clause to such a dramatic degree that it first needed the Legislature’s approval.

Last November Californians voted on either allowing or rejecting same-sex marriage in a citizen initiated proposition, Proposition 8, resulting in a No vote of 52 per cent.

Proposition 8 superseded the Supreme Court’s May 2008 ruling that legalized same-sex unions in California by changing the state constitution to outlaw them.

Gay rights advocates have scheduled marches throughout California and in several other states for this evening to protest the court’s ruling.

In the past, citizen initiated proposals in California have restricted how California’s legislature may raise and spend funds, limited the number of terms members may serve, declared English the official language, repealed state-level affirmative and bilingual education programmes, and over-ruled the state’s decision to dispose of toxic waste in Italy in 1987.

They have also imposed taxes on tobacco products, regulated toxic chemicals, mandated a fixed proportion of the state budget be spent on education, and raised the minimum wage.