A federal district court judge today struck down California’s ban on gay marriage, ruling that the prohibition violates the U.S. Constitution. The decision, which is expected to be appealed, represents the first time a federal judge has ruled that the U.S. Constitution protects the right of same-sex couples to marry.

In his ruling, District Court Judge Vaughn Walker stated that gay and lesbian couples enjoy a fundamental right to marry. This right, according to Walker, is protected by both the Due Process and Equal Protection clauses of the Constitution’s 14th Amendment.

The case, Perry v. Schwarzenegger, was prompted by the passage of Proposition 8, a 2008 California ballot initiative that amended the state constitution to prohibit same-sex marriage. In striking down that language, Walker said that it served no real purpose beyond discriminating against same-sex couples. “Proposition 8 does nothing more than enshrine in the California Constitution the notion that opposite sex couples are superior to same sex couples,” he wrote, adding: “Because Proposition 8 prevents California from fulfilling its constitutional obligation to provide marriages on an equal basis, the court concludes that Proposition 8 is unconstitutional.”

Proposition 8 had survived an earlier challenge in state court. That case went all the way to the California Supreme Court, which, in May 2009, ruled that Proposition 8 was valid.

Just days before the state Supreme Court’s ruling, a new lawsuit challenging Proposition 8 was filed in federal district court in California by a number of gay couples who had attempted to marry and had been turned away by state officials. The suit alleged that Proposition 8 violates the Due Process and Equal Protection clauses of the 14th Amendment of the U.S. Constitution because it denies gays and lesbians the fundamental right to marry.

The trial, which opened in a federal courthouse in San Francisco in January 2010, attracted a lot of media attention, and not just because of its historic nature. Working together to overturn Proposition 8 was the legal odd couple of Ted Olson, former solicitor general in the George W. Bush administration, and David Boies, a longtime Democratic lawyer. The two had made headlines a decade earlier when they represented opposite sides in Bush v. Gore, the U.S. Supreme Court case that ultimately resolved the 2000 presidential election dispute in Florida in Bush’s (and Olson’s) favor.

At trial in the Perry case, Boies and Olson argued that depriving gays and lesbians of their fundamental right to marry is harmful to them and their children and that there is no legitimate reason to deny them this right. Arguing in defense of Proposition 8, attorney Andrew Pugno stated that it was up to the people of the state to decide whether to expand marriage rights and that Californians’ vote to prohibit same-sex marriage should be respected.

The case now moves to the U.S. 9th Circuit Court of Appeals. Many legal scholars have stated that if the 9th Circuit affirms Judge Walker’s decision, the case will likely end up before the U.S. Supreme Court.

The Pew Forum offers a number of resources that explain different aspects of the same-sex marriage debate. These include:

The full text of the decision is available on the court’s website.

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