Senate Democrats introduce legislation to repeal the Defense of Marriage Act, a law the Obama administration says it will not defend in court. House Republicans have mounted their own legal defense of the act. The measure prevents gay couples from receiving federal rights extended to heterosexual couples.Democrats introduced legislation Wednesday that would repeal the Defense of Marriage Act, a renewed attack on the 15-year-old law the Obama administration has said it would no longer defend in court from challenges brought on behalf of same-sex couples.