Via New York Lawyer (subscription required):

A federal magistrate judge has permitted Congress to intervene in a case challenging the Defense of Marriage Act as unconstitutional. Southern District Magistrate Judge James C. Francis issued a 12-page order and memorandum yesterday saying Congress has a right to intervene in Windsor v. United States, 10 Civ. 8435, now that the U.S. Justice Department has said it will no longer argue that the act is constitutional.