Prop 8 Ruling Due TODAY

U.S. District Judge Vaughn Walker

Chief U.S. District Judge Vaughn Walker of San Francisco will decide whether Proposition 8, the November 2008 initiative that defined marriage as the union of a man and a woman, violated gays’ and lesbians’ right of equality under the U.S. Constitution.

After court officials on Tuesday announced plans to release the decision, Prop. 8′s sponsors filed papers making it clear they expect to lose this round. They asked Walker, if he rules against them, to leave the ban on same-sex marriages in place while they appeal.

Lawyers for Prop. 8′s backers told the judge they were confident that any such ruling would be overturned on appeal. They said a stay would honor the will of the voters and would not harm same-sex couples, who can still register as domestic partners.

Walker presided over a nonjury trial in January, the first ever held in a federal court on the issue. The plaintiffs, two gay men from Burbank and two lesbians from Berkeley, testified that their hopes to be married were thwarted when voters overturned the May 2008 state Supreme Court ruling that legalized same-sex marriage.

The plaintiffs’ witnesses also included researchers who said sexual orientation has no relationship to successful parenting and that marriage in the United States is an evolving institution.

The conservative religious coalition that sponsored Prop. 8 offered testimony that the male-female definition of marriage is universal and that children are better off with married, biological parents.

The city of San Francisco joined the lawsuit on the plaintiffs’ side. Attorney General Jerry Brown declined to defend Prop. 8 and said he considers it unconstitutional.

Walker’s ruling, due sometime between 1 p.m. and 3 p.m., is certain to be appealed to the Ninth U.S. Circuit Court of Appeals in San Francisco. The case could reach the U.S. Supreme Court in 2011 or 2012.

A group that supports same-sex marriage has announced a march from the Castro District to City Hall, starting at 5 p.m., followed by a rally from 6:45 to 8 p.m.

Read more: SF Gate