Courtesy of SCOTUSblog, here's a plain English take on Hollingsworth v. Perry, the challenge to the constitutionality of California's Proposition 8, which bans same-sex marriage:

After two same-sex couples filed their challenge to Proposition 8 in federal court in California, the California government officials who would normally defend the law in court, declined to do so. So the proponents of Proposition 8 stepped in to defend the law, and the California Supreme Court ruled that they could do so under state law. But today the Supreme Court held that the proponents do not have the legal right to defend the law in court. As a result, the decision by the U.S. Court of Appeals for the Ninth Circuit has no legal force, and the Supreme Court sent the case back to the appeals court with instructions to dismiss the case.