Michigan's witness in gay-marriage trial barred

      The state of Michigan's defense of a ban on gay marriage is off to a rocky start after a judge refused to allow the first witness to testify.

      Sherif Girgis is a law student at Yale University and a doctoral candidate at Princeton University. He has written and talked about a historical defense of marriage between a man and a woman.

      Federal Judge Bernard Friedman says Girgis will be an expert witness - someday. Friedman says Girgis' opinions won't help him decide this case.

      Two Detroit-area women are challenging Michigan's ban on same-sex marriage, which was approved by voters in 2004.

      The state attorney general's office is defending the amendment this week and asked for a break Monday to summon another witness.