SAN FRANCISCO — U.S. District Judge Jeffrey White set the tone quickly in a hearing today in a case that could test the constitutionality of the Defense of Marriage Act.

White quoted President Obama on the campaign trail calling DOMA “abhorrent” because it’s discriminatory. The judge said he didn’t intend for his quoting the president to suggest he’d reached a decision on the legal issues of the case. But it indicated — along with his persistent questioning of a Department of Justice lawyer — a deep skepticism toward the government’s dogged defense of the federal law.