In the SanFran Chronicle:

Congressional Republicans have opened their defense of a law denying federal benefits to same-sex spouses in a San Francisco court, praising traditional marriage and slamming President Obama for abandoning the 1996 statute.

In papers filed with a federal judge, a lawyer chosen by House Republican leaders to back the Defense of Marriage Act in the nation's courts suggested Obama acted illegally by declaring in February that he considered the law unconstitutional and would no longer defend it.

"The president's constitutional duty to 'take care that the laws be faithfully executed' ... surely includes the duty to defend as well as enforce the law," said the attorney, Paul Clement, a former U.S. solicitor general under President George W. Bush.

... Clement's brief, filed last Friday, went further. Congress, he said, could legally withhold benefits from gay and lesbian couples because "opposite-sex marriage is a deeply rooted, historic institution - and a fundamental constitutional right - and same-sex marriage is neither of these things."Congress could also rely on "basic biological differences," Clement said, because only opposite-sex couples are capable of having children, and "encouraging child-rearing by a married mother and father is a legitimate governmental interest."