It’s set to drop sometime between 4 p.m. and 7 p.m. ET, and since it’s sure to be the story of the day, let’s get a thread up now for rapid reaction when it does. The suspense mounts: Will Judge Vaughn Walker hand conservatives a legal victory by upholding Prop 8 against Ted Olson’s and David Boies’s equal protection challenge? Or will he hand conservatives a political victory by striking the law down, thereby irritating the (decreasing) majority nationwide that opposes gay marriage and giving the GOP an irresistible midterm talking point about “activist judges”? Heads you win, tails they lose. Unless of course you’re noted gay-marriage opponent Barack Obama, who I’m betting will be oddly downbeat if Walker vindicates his ostensible position by upholding the law.

While we wait, you can read Olson’s opening statement at the trial here. The key line for legal purposes is “There is no rational justification for this unique pattern of discrimination.” In any equal protection case, there are three levels of scrutiny: (1) strict scrutiny, which applies to laws that discriminate based on race or religion; (2) intermediate scrutiny, which applies to laws that discriminate based on gender; and (3) rational-basis review, which applies to all other forms of discrimination, especially economic. Basically, a law that falls into the first category is always unconstitutional, a law that falls into the second is sometimes unconstitutional (it depends on the specifics), and a law that falls into the third is almost always constitutional. Because the Supreme Court has never held that gays are a “suspect class” and therefore deserving of the special protection of strict scrutiny, Olson had a choice of how to approach this. Either he could argue that they should be a suspect class, in which case Prop 8 would inevitably be struck down, or he could forget the suspect class stuff and argue that even under the lowest level of scrutiny — rational-basis review — Prop 8 should be struck down because denying marriage rights to gays serves no rational purpose. He apparently went the latter route, which is smart insofar as the Supremes will be reluctant to extend “suspect class” status any further than it already is and because Anthony Kennedy has already written two landmark decisions striking down anti-gay laws — one of which was explicitly based on rational-basis review. In other words, Olson already has his eye on this case landing in the high court and he’s playing for a 5-4 win with Kennedy as the deciding vote, figuring that if AK was willing to call discrimination against gays irrational once before, he’ll be willing to do so again.

So there’s the legal posture, and there’s your explanation why this case will assuredly be appealed to the (gulp) Ninth Circuit no matter which way it goes. Stand by for updates.

Update: My timing was perfect: Just as I hit publish on this post, the news broke that Walker has torpedoed Prop 8. No surprise. Waiting for the opinion.

Update: Okay, here’s the decision. The law was struck down on two grounds, both due process (page 109) and, as expected, equal protection (page 117). And as expected, the EP ruling is that there’s no rational basis for limiting marriage to straights.

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.

Update: The LA Times notes that even the witnesses who testified on behalf of Prop 8 made important concessions:

Backers of Proposition 8 contended that the legal burden was on the challengers to prove there was no rational justification for voting for the measure. They cited as rational a view that children fare best with both a father and a mother.

But defense witnesses conceded in cross-examination that studies show children reared from birth by same-sex couples fared as well as those born to opposite-sex parents and that marriage would benefit the families of gays and lesbians.

Update: Gabe Malor has another key excerpt from the opinion the lack of compelling witness testimony in defense of the law.

Update: CNN has a handy dandy guide to how this will make its way up to the ladder to the Supreme Court. First comes the three-judge hearing in the Ninth Circuit, then comes an en banc hearing of the entire court, and then presumably the Supremes will grant cert. Possibly … just in time for the 2012 election?

Update: A good point by Marc Ambinder on why the evidentiary portions of the ruling are arguably more important than the legal conclusions. Appellate courts can overrule the latter but they’re usually bound by the trial court’s findings of fact. So Walker’s finding, based on the testimony, that “Same-sex couples are identical to opposite-sex couples in the characteristics relevant to the ability to form successful marital union” should in theory also guide the Supreme Court.