An important trial begins in America’s fight over gay marriage

THE venue, gay-friendly San Francisco, may at first glance seem predictable for a legal challenge that may lead to the legalisation of gay marriage in America. But nothing else about the trial of Perry v Schwarzenegger, which began on Monday January 11th, fits stereotypes. Pitting both a male and female gay couple (including Kristin Perry) against the state of California (nominally represented by its governor, Arnold Schwarzenegger), it is a federal review of whether Proposition 8, a Californian voter initiative of 2008 that outlawed gay marriage in the state, is constitutional.

Whatever the outcome, the case is likely to go to appeal and come before the Supreme Court. But first the trial will do two things: it will establish, for the first time, a body of evidence, through expert testimony, that appelate courts can use to evaluate the claims by supporters and opponents of gay marriage. And it will blur the existing partisan divide on the issue between conservatives and liberals. …