California Supreme Court Justice Carlos Moreno—the sole justice to cast a vote against upholding Proposition 8—has unexpectedly announced his retirement. Moreno is the sole Democratic appointee and Latino on the court, and is described as the author of some of "its most important gay-rights opinions."

The San Jose Mercury News broke the story:

In an interview with the Mercury News on Thursday, the soft-spoken Moreno said the "time seemed right" to move on, citing Brown's election, reaching full judicial pension eligibility and being young enough to still explore lucrative options in the private sector.

Moreno's departure comes on the heels of the retirement this month of Chief Justice Ronald George, who has been replaced by new Chief Justice Tani Cantil-Sakauye. The two moves could usher in one of the most significant shifts on the court in decades, with Brown in position to fill Moreno's seat and perhaps others in the coming years on an aging Supreme Court.

The governor will be under pressure to replace Moreno with either a Latino or an African-American; there currently are no African-American justices on the court, and San Francisco appeals court Justice Martin Jenkins, a former federal judge, is already being circulated as a potential candidate.

Moreno has been the Court's fiercest advocate for LGBT rights, reports The san Francisco Chronicle.

Moreno said the rulings of which he is proudest include four 2005 decisions that upheld same-sex couples' parental rights, including custody and child support, and the right of domestic partners to be free of discrimination by businesses. He was also part of the 4-3 majority in May 2008 that declared the right of gays and lesbians to marry in California.

After voters overturned that ruling by passing Proposition 8 in November 2008, Moreno was the only dissenter in the court's 6-1 decision that declared the measure a valid amendment to the state Constitution. In his dissent, Moreno wrote that the ruling "places at risk the state constitutional rights of all disfavored minorities." Prop. 8 is now being challenged in federal court. "He has been a champion of ensuring the Constitution's protection of equality," said Geoff Kors, executive director of Equality California, the state's largest gay-rights group.

You'll recall that Moreno was on the Obama Administration's shortlist for the U.S. Supreme Court when it was considering replacements for David Souter. Moreno was interviewed by the President. The appointment went to Justice Sonia Sotomayor ... ironically  announced the same morning the Court released its Prop decision.

Some Background ...
Pro Gay Marriage Moreno on Obama's SCOTUS List?
CA Supreme Moreno Casts Single Vote Against Prop 8