The California Supreme Court struck down a ban on same-sex marriage on Thursday (May 15), making it possible that the state will become the second in the country, after Massachusetts, to recognize gay and lesbian marriages.

The 4-3 decision says that the current law "limiting the designation of marriage to a 'union between a man and a woman' is unconstitutional," and that so-called "domestic partnerships" for same-sex couples are discriminatory and not "constitutionally valid" in place of marriage. The justices also cited the legalization of interracial marriage in California back in the 1940s as a reason for striking down the ban.

The case goes back to 2004, when San Francisco Mayor Gavin Newsom allowed gay and lesbian couples to get married in that city. When the court halted the marriages, and eventually nullified them, the mayor, gay and lesbian organizations and 12 same-sex couples filed suits against the state.

Currently, same-sex couples in California can register as domestic partners and get the same legal rights as married, heterosexual couples, including the ability to divorce and seek child support. Connecticut, New Hampshire, New Jersey and Vermont also recognize civil unions that give most of the same rights as marriage but provide no federal legal protection.

California's State Legislature has twice passed bills to authorize same-sex marriage, but Governor Arnold Schwarzenegger vetoed them, saying he wanted to wait for the court to make its decision. Now that has happened, the battle is still not over. Opponents of same-sex marriage will try to pass either another ballot initiative defining marriage as between a man and a woman, or a state constitutional amendment that will do the same thing. Twenty-seven other states in the country have similar amendments.

But for now, gay-rights activists are enjoying this victory. A source inside San Francisco's City Hall said that after the ruling, Newsom sent an e-mail out to his staffers that read: "We won." And outside of the courthouse, couples were celebrating — some with champagne and some with their children.