Proposition 8, the ballot measure that halted same-sex marriage in California, is unconstitutional, U.S. District Court Chief Judge Vaughn Walker ruled this afternoon.

Here is the conclusion of the 135-page ruling:

Proposition 8 fails to advance any rational basis in singling out gay men and lesbians for denial of a marriage license. Indeed, the evidence shows Proposition 8 does nothing more than enshrine in the California Constitution the notion that opposite-sex couples are superior to same-sex couples.  Because California has no interest in discriminating against gay men and lesbians, and 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.

The case, Perry v. Schwarzenegger, is expected to be appealed and eventually reach the U.S. Supreme Court. A stay on marriages has been issued as the case continues through the appeals process.